US2469597A - Method of and apparatus for heating, sizing, or forming quartz tubes and profiles - Google Patents

Method of and apparatus for heating, sizing, or forming quartz tubes and profiles Download PDF

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US2469597A
US2469597A US644704A US64470446A US2469597A US 2469597 A US2469597 A US 2469597A US 644704 A US644704 A US 644704A US 64470446 A US64470446 A US 64470446A US 2469597 A US2469597 A US 2469597A
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heating
tube
forming
shell
tubular
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Guigas Gustav
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    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03BMANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B23/00Re-forming shaped glass
    • C03B23/04Re-forming tubes or rods
    • C03B23/047Re-forming tubes or rods by drawing
    • C03B23/0476Re-forming tubes or rods by drawing onto a forming die, e.g. a mandrel or a wire
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S65/00Glass manufacturing
    • Y10S65/04Electric heat

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  • My invention relates to a method of and apparatus for heating, sizing, or forming quart-z tubes and profiles.
  • An important object of the invention is to provide electrically operated means for heating the quartz tubes or profiles, thus eliminating the objectionable gas oxygen burner, which burner produces a method which is slow, costly and noisy.
  • a further object of the invention is to provide apparatus of the above mentioned character so constructed that the quartz tube or profile may be quickly and easily introduced into the electric heating unit or furnace and may be conveniently manipulated therein for heating, sizing, or forming.
  • a further object of the invention is to provide a cover automatically moved in position to close the opening in the side of the electric heating unit, after the tube or profile has been introduced into the heating unit.
  • a further object of the invention is to provide apparatus of the above mentioned character which is compact and relatively simple in construction and cheap to manufacture.
  • a further object of the invention is to provide apparatus of the above mentioned character so constructed that the adjustment of the heat in both the heating shell and mandrel may be obtained by shifting the mandrel into and out of the magnetic field.
  • a further object of the invention is to provide apparatus of the above mentioned character which is automatic, to some extent.
  • FIG 1 is an end elevation of apparatus embodying my invention
  • Figure 2 is a perspective view of the same.
  • FIG. 3 is a transverse section taken on line 3-3 of Figure 4,
  • Figure 4 is a longitudinal section taken on line 4-4 of Figure 3,
  • Figure 5 is a perspective view of the high frequency tubular coil
  • Figure 6 is a perspective view of a device embodying a modified form of the invention.
  • Figure 7 is a central vertical longitudinal sec-- -tion through apparatus embodying a further modification of the invention.
  • Figure 8 is an end elevation of the same
  • Figure 9 is a transverse section taken on line 9-9 of Figure 7,
  • Figure 10 is a similar view taken on line IU-
  • Figure 11 is a longitudinal vertical section taken on line H-H of Figure 9 and,
  • Fig. 12 is a side elevation of a circular disc.
  • the numeral 23 designates an electrical heating unit or furnace as a whole.
  • This heating unit comprises vertical ends 2! formed of refractory material. These ends are secured in place by brackets 22, rigidly attached thereto, and these brackets are rigidly mounted upon a horizontal refractory base 23, mounted upon a table top 24 or the like.
  • are provided near their tops with circularly curved openings 25 for receiving outer annular flanges 26, integral with circular discs 27, formed of refractory material. These circular discs also have inner circularly curved flanges 23.
  • is an outer cylindrical casing 29, formed of refractory material, and this casing receives the discs 21, and is held in place thereby.
  • the numeral 30 designates an inner cylindrical casing, arranged between the disc 27 and receiving the inner flanges 28, and held in place thereby.
  • This inner casing is provided upon its inner surface with circumferentially extending grooves 3
  • the inner casing 30 is arranged in spaced concentric relation to the outer casing 29, alfording a cylindrical chamber or space 33, for receiving a tubular water cooled high frequency coil 34, preferably formed of copper.
  • This coil extends circumferentially around the major portion of the circumference of the inner casing 33, but is shaped to provide a main longitudinal side opening or passage, Figure 5.
  • a coolant is passed through the coil 34 and the opposite ends of the coil are connected with a suitable source of high frequency current.
  • the numeral 35 designates a heating tubular shell, formed of carbon or graphite, or a mixture of the same, or any other suitable material. This heating shell is arranged between the ends of the flanges 23 and is positioned within the inner refractory casing 30 and is held in place thereby. The elements 29, 30, and 35 are all retained in concentric relation.
  • have vertically inclined radial openings 38, which lead to the circularly curved openings 25.
  • the discs 21 have inclined radial openings 27', in registration with the openings 36.
  • the outer casing 29 has a longitudinal opening 31
  • the inner casing has a longitudinal opening 38
  • the heating shell 35 has a longitudinal opening 39.
  • Rigidly' mounted upon the sheet or base 23 are vertical brackets 4
  • Rigidly mounted upon the rock shaft 43 are radial swinging arms 44, provided at their free ends with U-shaped sockets'45, preferably having linings 46 of refractory material. These sockets face upwardly and are open at their tops and are substantially vertical when the arms are in the rearmost position.
  • Rigidly mounted upon'the rock shaft 43 are radial arms 41, to the 'free ends of which are rigidly secured a door or cover 48, adapted to enter the longitudinal opening 31.
  • This door or cover is formed of refractory :ma terial andwhen in the closed position; will cover the opening 37 and properly confine the heat within the heating unit or furnace.
  • a protecting screen 49 Arranged in front'of the heating unit or furnace 28 is a protecting screen 49, having a dark glass window 55.
  • the arm or arms 44 are grasped by the operator and swung forwardly and may beheld in the forward position.
  • the current is turned on, and the high frequency coil 34 induces current in the carbon heating shell35, which is heated to a bright heat.
  • the operator places the quartz tube or profile 40 within the-sockets 45 and then swings the arms 44 rearwardly. These arms move the tube laterally through the several longitudinal openings 31, 38, and 39 and position the same within the carbon heating shell 35,. inspaced concentric relation thereto.
  • the arms 41 are also moved rearwardly and the door 48 covers the opening 3'1, and the turning movement of the rock shaft is limited by the arms 41 contacting with the outer casing 29.
  • the tube 49 is thus supported within the heating shell 35, and may be turned, rnoved longitudinally or otherwise manually manipulated by the operator, who may observe the operation through the dark window 50.
  • the heatfrom the shell 35 heats the tube 40, which may be plasticized for sizing or forming
  • the extent of the heat treatment'of the tube would of course be regulated by the point to which the shell 35 is heated and also to the length of time thatthe tube remains within the heating'shell.
  • the tube, during the heat treatment may be readily shifted to the exterior of the heating unit for inspection, and returned therein.
  • the numeral 55 designates a horizontal rock shaft, journaled in bearings 56, formed upon vertical brackets 51, rigidly attached to the sheet 23. These brackets are provided at their upper ends with upwardly facing U-shaped sockets 58, having -cal with-those shown and described in connection with the first form of the invention.
  • the tube 40 is introduced into the sockets El and when the arms 60 are swung rearwardly, the tube passes laterally into the heating shell and also enters the sockets 58 and is held thereby in spaced concentric relation to the heating shell '3 5.
  • the heating shell heats the tube which is plasticized and may be formed or sized.
  • a heating unit or furnace 66 is shown, including ends 2 I, corresponding to the ends 2
  • An outer casing 29' is'provided, corresponding'to the outer casing 23, an inner casing. 30, corresponding to the casing 30 and a tubular heating, sizing or forming shell 35, corresponding somewhat-to the heating shell 35.
  • the outer casing 29' does not have the longitudinal slot 31 and the inner casing does not have the longitudinal opening-39. These outer and inner casings have continuous periphcries and are openat their ends.
  • the tubular heating shell does not have the opening 39 and its periphery is continuous, while'its'ends are open.
  • the discs 21 have inclined orbeveled faces 61.
  • The-heating shell 35- has a cylindrical bore 38, leading into a taperedportion 69,fiaring outwardly.
  • the heating shell 35'- is formed of carbon, graphite, or the like.
  • the numeralJEl designates a formingor 6X- panding mandrel, which is longitudinally tapered, increasing in-diameter outwardly.
  • This mandrel may be formed of carbon or graphite.
  • This mandred is-arranged to enterthe bore of thezheating shell 35', and is smaller in diameter than :the heating shell 35 in diametenendis arranged in spaced concentric relation to the heating: shell.
  • the mandrel i0 is rigidly mounted'uponv a horizontal supporting rod 1 I, mounted within an opening 12 formed in a stationary bracket 13; and clamped in the selected adjusted position'by aset screw 14.
  • the numeral 15 designates acarriage having a depending portion 15, preferably formed integral therewith. This depending portion has bearings 16, receiving transverse'shafts 11, carrying wheels 18. These wheels are arranged to travelupona stationary track including horizontal. rail 18, havingupstanding guidefianges 80.
  • the ends 2 l 5 are rigidly mounted upon the carriage 15 by brackets 8 I.
  • Each post 85 is equipped with an adjustable chuck, including a tubular socket 88, formed integral therewith.
  • This tubular socket has a cylindrical bore 81, having a tapered portion 88.
  • Slips 89 are mounted in the cylindrical bore 87 and have tapered portions to engage with the tapered bore portion 88, and these slips are screw threaded, as shown at SI, for engaging a clamping ring 92.
  • These adjustable chucks are adapted for clamping engagement with the tube to be heated, for moving the same longitudinally.
  • Means are provided to cause the carriages 82 to move longitudinally in unison, comprising an endless sprocket chain 93, passing about sprocket wheels 05, carried by shafts 96, journalled in fixed bearings 97.
  • One shaft 95 is power driven.
  • This sprocket chain is horizontally arranged and its upper run is attached to the carriages 82, as shown at 98. This upper run extends through a horizontal passage 88 formed in the depending portion it and is free from connection with the carriage 15.
  • Means are provided to shift the heating unit 88 and carriage l longitudinally, comprising a transverse horizontal shaft I 02, journalled in a bearing I03, formed in the depending portion 16.
  • This shaft projects outwardly beyond one side of the carriage and the tracks and is equipped with a hand Wheel I04.
  • the shaft I02 has a pinion rigidly mounted thereon, engaging a stationary rack I88, which is rigidly attached to the ad- J'acent rail 70.
  • the hand wheel I 04 By turning the hand wheel I 04, the pinion 105 will travel upon the rack l 06, thereby causing the carriage to be adjusted longitudinally in the desired direction.
  • Any suitable means may be employed to hold the shaft I 02 against improper turning movement.
  • the clamping nuts 92 are unscrewed so that the chucks are expanded.
  • the quartz tube I0! is passed through the right chuck, Figure 7, and its free end introduced into the end of the heating shell 35' and brought into contact with the reduced end of the tapered mandrel, which pro- J'ects in the same for a short distance.
  • the current is turned on and the high frequency coil heats the tubular shell 35' and the mandrel I0 to to a bright heat.
  • the mandrel remains sta tionary and the carriage is stationary during the sizing or forming.
  • the carriage 15 may be longitudinally adjusted with relation to the mandrel to vary the distance between the mandrel 10 and the tapered bore portion 89, to regulate the extent of forming or sizing.
  • This adjustment also brings the mandrel different distances into the heating shell 35 and this has been found to regulate the degree of heat of the furnace, to a certain extent.
  • the tube With the mandrel I0 and heating unit or furnace held stationary, the tube may be manually fed into the right end of the heating shell 5 and through this heating shell and about the mandrel l0 and becomes sized or formed to a larger diameter.
  • the plasticized portion of the tube now passes beyond the left end of the furnace I58 and will freeze and may be brought into the left chuck.
  • the current may be turned off, while the tube is being clamped within the chucks, which is the next step.
  • the heat is again turned on and the two carriages 82 are moved in unison to the left longitudinally of the mandrel.
  • the sizing or forming of the tube about the mandrel is continuous during the travel of these carriages.
  • the carriages 82 push and pull the tube.
  • the operation is continued until the carriage 82 to the right reaches a point near the furnace 82.
  • the current is turned off, the heating unit 66 is shifted to the right to uncover the mandrel 18.
  • the plasticized portion of the tube adjacent to the mandrel T0 freezes, the short right end of the tube may be cracked off, and the formed tube separated from the mandrel.
  • Apparatus for heating, forming or sizing quartz tubes or the like comprising a heating unit, said heating unit comprising a heating shell to be heated by electrical induction, said heating shell having a side opening, a high frequency coil surrounding the heating shell and having a side opening disposed adjacent to the first named side opening, the quartz tube to be heated being passed laterally through the side openings into the heating shell.
  • Apparatus for heating, forming or sizing quartz tubes or the like comprising a refractory casing including an outer casing, an inner casing, a tubular heating shell arranged within the inner casing, the outer casing, inner casing and tubular shell having side openings in substantial alignment, and a tubular high frequency coil arranged between the outer and inner shells, the tube being moved into the tubular heating shell by a lateral movement of the same.
  • Apparatus for heating, forming or sizing quartz tubes or the like comprising a refractory casing including outer and inner casings, a tubular heating shell arranged within the inner casing, the outer casing, inner casing and tubular shell having side openings in substantial alignment, a high frequency coil arranged between the outer and inner shells, the tube being moved into the tubular heating shell by a lateral movement, and means to support the tube when introduced into the tubular heating shell.
  • Apparatus for heating, forming and sizing quartz tubes or the like comprising a heating unit including a refractory housing, said housing comprising ends having openings, discs arranged upon the inner sides of the ends and provided with openings and having outer flanges to enter the openings and inner flanges, an outer casing arranged between the ends and surround ings the discs and held in place thereby, an inner casing arranged between the discs and spaced from the outer casing and engaging the inner flanges and held in place thereby, high frequency coil arranged between the inner and outer casings, a tubular heating shell arranged between the inner flanges and held in place by the inner casing, the outer and inner casings and the heating shell have openings in their sides and the ends and discs having radial openings leading to their first named openings, the tube being moved into the tubular heating shell by a lateral movement.
  • Apparatus'ior heating, forming and sizing quartz tubes or the like comprising a-refractory housing including ends having openings, discs disposed upon the inner sides of the ends and provided with openings and having outer flanges to enter the openings of the ends andhaving inner flanges, an outer casing arranged between the ends and engaging the discs and held inplace thereby, an inner casing spaced from the outer casing and arranged between the endsand engaging the inner fianges to be held in place thereby, a high frequency coil arranged between the outer and inner casings, a tubular heating shell to be heated by electrical induction arranged within the inner casing between the inner flanges and held in place by the inner casing, and means for introducing the tube into the tubular heating shell.
  • Apparatus for heating, forming and sizing quartz tubes or the like comprising a refractory housing, said housing having a side opening, a tubular heating shell held within the housin to be heated by electrical induction and having a side opening, a movable door to cover the side opening in the tubular heating shell, and means for supporting the tube when introduced into the tubular heating shell.
  • Apparatus for heating, forming and sizing quartz tubes or the like comprising a refractory housing having a side opening, a tubular heat ing shell arranged within the refractory housing to be heated by electrical induction and having a side opening, a door to cover the side opening in the tubular heating shell, means to receive the tube and introduce the same into the tubular heating shell through the side openings, and means connecting the door with the first named means so that the door is moved by the first named means,
  • Apparatus for heating, forming and sizing quartz tubes or the like comprising a refractory housing having a side opening, a tubular electrical heating shell arranged within the housing to be heated by electrical induction and having a side opening, a rock shaft, means mounted upon the rock shaft for holding the tube and passing the same into the heating shell through the side openings, a door to cover the side opening of the tubular heating shell, and operating means connecting the door and rock shaft,
  • Apparatus for heating, forming or sizing quartz tubes or the like comprising an electricalheating unit including a refractory housing, said housing comprising a periphery and ends, said periphery having a side opening and the ends having radial openings, a tubular heating shell arranged within the housing to be heated by electrical induction and having a side opening, a coil to heat the heating shell, a rock shaft arranged near and upon one side of the housing, arms secured to the rock shaft and arranged near and outwardly of sockets to receive the tube, the sockets being adapted to pass the tube into the tubular heating shell, a cover, and arms carrying the cover and mounted upon the rock shaft.
  • an electricalheating unit including a refractory housing, said housing comprising a periphery and ends, said periphery having a side opening and the ends having radial openings, a tubular heating shell arranged within the housing to be heated by electrical induction and having a side opening, a coil to heat the heating shell,
  • Apparatus for heating, forming or sizing quartz tubes or the he comprising a refractory housing including a periphery and ends, said periphery having a side opening and the ends having radial openings, a tubular heating'shell arranged-within the housing and having'a side the ends and having opening, a high frequency coil arranged within the housing adjacent to the tubular heating shell, a rock shaft disposed upon one side of the periphery, arms mounted upon the rock shaft and arranged near and upon the outer side of the ends and having sockets to receive the tube and move the same into the tubular heating shell, guide means mounted upon the housing, rails" mounted to travel upon the guide means, a door to cover the side opening in the tubular heating shelland carried by the rails, and operating connecting means between the rails and rock shaft.
  • Apparatus for heating, forming or sizing quartz tubes'or the like comprising a refractory housing including a periphery and ends, said periphery having a side opening and the ends havingradial openings, a tubular heating shell arranged within the housing and having a side opening, a coil arranged within-the housing adjacent to the tubular heating shell, a rock shaft disposed upon one side of the periphery, arms mounted upon the rockshaft and arranged near and upon the outer-sides of the ends and having sockets to receive the tube and move the same into the tubular heating shell, guide means mounted upon the housing, rails mounted to travel upon the guide means, a door to cover the side opening in the tubular heating shell and carried by the rails, operating connecting means between the rails and rock shaft, and stationary sockets to receive the tube when it is introduced into the tubular heating shell.
  • Apparatus for heating, forming'or sizing quartz tubes or the like comprising a heating unit including a refractory casing, a tubular heating shell to be heated by electrical induction arranged within the casing-and having a tapered forming bore, the tapered forming bore increasingin diameter toward its outlet end, a tapered forming mandrel to enter the tapered forming bore of the tubular heating shell, the tapered forming mandrel increasing in diameter toward the outlet end of the tapered forming bore and having a reduced end smaller than the normal diameter of the tube and a large end having a greater diameter than such normal bore; a coil arranged adjacent to the tubular heating shell, carriages arranged upon the opposite sides of the heatingunit, means mounted upon the carriages to receive'and hold thetube and move the same longitudinally, and means to move at least one carriage, the arrangement being such that the tapered forming mandrel increases the diameter of the plasticized portion of the tube when the tube is moved longitudinally and presses the outer faced the tube into contact
  • Apparatus for heating, forming or sizing quartz'tubes or the like comprising a heating unit including a refractory casing, a tubular heating shell mounted within the refractory casing and having a tapered forming bore and adapted to be heated by electrical induction, said tapered forming bore increasing in diameter toward its outlet end, a coil arranged adjacent to the tubular heating shell, a tapered forming mandrel toenter the tapered forming bore of th'e' tubular heating shell, the tapered forming mandrel having a reduced end of smaller diameter than the original bore of the tube and 'a large'end of greater diameter than such bore, adjustable means to eifect'a relativelongltudinal movement between the mandrel and tubular heating shell, and means to support the tube and moveable longitudinally of the mandrel, the arrangement being such that the tapered form ing mandrel increases the bore of the plasticized portion of the tube when the tube is moved longitudinally over it and presses the outer
  • Apparatus for heating, forming or sizing quartz tubes or the like comprisin a track, a carriage mounted upon the track to move longitudinally thereof, a heating unit mounted upon the carriage and including a refractory housing, a tubular heating shell mounted within the housing and adapted to be heated by electrical induction and having a tapered forming bore which increases in diameter toward its outlet end, a tapered forming mandrel to enter the tapered forming bore of the tubular electrical heating shell, the tapered forming mandrel increasing in diameter toward the outlet end of the tapered forming bore and having a reduced end of smaller diameter than the original bore of the tube and an enlarged portion of a greater diameter than such original bore, means to hold the mandrel stationary, coil disposed in cooperative relation to the tubular heating shell and the mandrel, means to move the carriage longitudinally of the track, carriages mounted upon the track to travel longitudinally thereof and arranged upon the 10 opposite sides of the heating unit, means carried by the last named carriages for receiving and holding the tube, and

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Description

May 10, 1949. G. GUIGAS METHOD OF AND APPARATUS FOR HEATING, SIZING, OR
FORMING QUARTZ TUBES AND PROFILES 4 Sheets-Sheet 1 Filed Feb. 1, 1946 2,469,597 SIZING, OR
I 4 Sheets-Sheet 2 2-3 7 K l/ \yf GUIGAS FORMING QUARTZ TUBES AND PROFILES Jiwenior;
Gustav GEL 9w)" May 10, 1949.
METHOD OF AND APPARATUS FOR HEATING,
Filed Feb. 1, 1946 Main ,LXEEEM Z H L 7 H m 6 2 2 w 2 M 2 G. GUIGAS METHOD OF AND APPARATUS FOR HEATING, SIZING, OR
May 10, 1949.
FORMING QUARTZ TUBES AND PROFILES 4 Sheets-Sheet 5 Filed Feb. 1, 1946 2,469,597 SIZING, OR FILES May 10, 1949. G. GUIGAS METHOD OF AND APPARATUS FOR HEATING FORMING QUARTZ TUBES AND PRO 4 Sheets-Sheet 4 Filed Feb. 1, 1946 fims'iav fi'uig w.
Patented May 10, 1949 UNITED STATES PATENT OFFICE METHOD OF AND APPARATUS FOR HEAT- IN G, SIZING, OR FORMING QUARTZ TUBES AND PROFILES 14 Claims.
My invention relates to a method of and apparatus for heating, sizing, or forming quart-z tubes and profiles.
An important object of the invention is to provide electrically operated means for heating the quartz tubes or profiles, thus eliminating the objectionable gas oxygen burner, which burner produces a method which is slow, costly and noisy.
A further object of the invention is to provide apparatus of the above mentioned character so constructed that the quartz tube or profile may be quickly and easily introduced into the electric heating unit or furnace and may be conveniently manipulated therein for heating, sizing, or forming.
A further object of the invention is to provide a cover automatically moved in position to close the opening in the side of the electric heating unit, after the tube or profile has been introduced into the heating unit.
A further object of the invention is to provide apparatus of the above mentioned character which is compact and relatively simple in construction and cheap to manufacture.
A further object of the invention is to provide apparatus of the above mentioned character so constructed that the adjustment of the heat in both the heating shell and mandrel may be obtained by shifting the mandrel into and out of the magnetic field.
A further object of the invention is to provide apparatus of the above mentioned character which is automatic, to some extent.
Other objects and advantages of the invention will be apparent during the course of the following description.
In the accompanying drawings forming a part of this application, and in which like numerals are employed to designate like parts throughout the same,
Figure 1 is an end elevation of apparatus embodying my invention,
Figure 2 is a perspective view of the same.
Figure 3 is a transverse section taken on line 3-3 of Figure 4,
Figure 4 is a longitudinal section taken on line 4-4 of Figure 3,
Figure 5 is a perspective view of the high frequency tubular coil,
Figure 6 is a perspective view of a device embodying a modified form of the invention,
Figure 7 is a central vertical longitudinal sec-- -tion through apparatus embodying a further modification of the invention,
Figure 8 is an end elevation of the same,
Figure 9 is a transverse section taken on line 9-9 of Figure 7,
Figure 10 is a similar view taken on line IU-|0 of Figure '7,
Figure 11 is a longitudinal vertical section taken on line H-H of Figure 9 and,
Fig. 12 is a side elevation of a circular disc.
In the drawings, wherein for the purpose of illustration are shown preferred embodiments of my invention, attention being called first to Figures 1 to 5 inclusive, the numeral 23 designates an electrical heating unit or furnace as a whole. This heating unit comprises vertical ends 2! formed of refractory material. These ends are secured in place by brackets 22, rigidly attached thereto, and these brackets are rigidly mounted upon a horizontal refractory base 23, mounted upon a table top 24 or the like.
The ends 2| are provided near their tops with circularly curved openings 25 for receiving outer annular flanges 26, integral with circular discs 27, formed of refractory material. These circular discs also have inner circularly curved flanges 23. Arranged between the ends 2| is an outer cylindrical casing 29, formed of refractory material, and this casing receives the discs 21, and is held in place thereby. The numeral 30 designates an inner cylindrical casing, arranged between the disc 27 and receiving the inner flanges 28, and held in place thereby. This inner casing is provided upon its inner surface with circumferentially extending grooves 3|, providing ribs 32. The inner casing 30 is arranged in spaced concentric relation to the outer casing 29, alfording a cylindrical chamber or space 33, for receiving a tubular water cooled high frequency coil 34, preferably formed of copper. This coil extends circumferentially around the major portion of the circumference of the inner casing 33, but is shaped to provide a main longitudinal side opening or passage, Figure 5. A coolant is passed through the coil 34 and the opposite ends of the coil are connected with a suitable source of high frequency current.
The numeral 35 designates a heating tubular shell, formed of carbon or graphite, or a mixture of the same, or any other suitable material. This heating shell is arranged between the ends of the flanges 23 and is positioned within the inner refractory casing 30 and is held in place thereby. The elements 29, 30, and 35 are all retained in concentric relation.
The ends 2| have vertically inclined radial openings 38, which lead to the circularly curved openings 25. The discs 21 have inclined radial openings 27', in registration with the openings 36. The outer casing 29 has a longitudinal opening 31, the inner casing has a longitudinal opening 38, and the heating shell 35 has a longitudinal opening 39. These longitudinal openings are in alignment and permit of the quartz tube or profile 40 being shifted laterally into and out of the heating shell 35.
Rigidly' mounted upon the sheet or base 23 are vertical brackets 4|, provided at their tops with bearings 42, for receiving a horizontal rock shaft 43. Rigidly mounted upon the rock shaft 43 are radial swinging arms 44, provided at their free ends with U-shaped sockets'45, preferably having linings 46 of refractory material. These sockets face upwardly and are open at their tops and are substantially vertical when the arms are in the rearmost position. Rigidly mounted upon'the rock shaft 43 are radial arms 41, to the 'free ends of which are rigidly secured a door or cover 48, adapted to enter the longitudinal opening 31. This door or cover is formed of refractory :ma terial andwhen in the closed position; will cover the opening 37 and properly confine the heat within the heating unit or furnace.
Arranged in front'of the heating unit or furnace 28 is a protecting screen 49, having a dark glass window 55.
The operation of the apparatus is as follows:
The arm or arms 44 are grasped by the operator and swung forwardly and may beheld in the forward position. The currentis turned on, and the high frequency coil 34 induces current in the carbon heating shell35, which is heated to a bright heat. The operator then places the quartz tube or profile 40 within the-sockets 45 and then swings the arms 44 rearwardly. These arms move the tube laterally through the several longitudinal openings 31, 38, and 39 and position the same within the carbon heating shell 35,. inspaced concentric relation thereto. When the arms are moved rearwardly the arms 41 are also moved rearwardly and the door 48 covers the opening 3'1, and the turning movement of the rock shaft is limited by the arms 41 contacting with the outer casing 29. The tube 49 is thus supported within the heating shell 35, and may be turned, rnoved longitudinally or otherwise manually manipulated by the operator, who may observe the operation through the dark window 50. The heatfrom the shell 35 heats the tube 40, which may be plasticized for sizing or forming The extent of the heat treatment'of the tube would of course be regulated by the point to which the shell 35 is heated and also to the length of time thatthe tube remains within the heating'shell. The tube, during the heat treatment, may be readily shifted to the exterior of the heating unit for inspection, and returned therein.
In Figure 6, I have shown a modification of the invention. In this figure, the ends 2| have rollers arranged upon their outer sides and rotatably mounted thereon. These rollers support circularly curved rails 52, having -stops 53, forming a passage between them. Rigidly secured to corresponding ends of these railsis a door 54, formed of refractory material, and arranged to travel circumferentially of the outer casing'23, exteriorly thereof. 'This door is adapted to cover the longitudinal opening 31 of the casing 29.
The numeral 55 designates a horizontal rock shaft, journaled in bearings 56, formed upon vertical brackets 51, rigidly attached to the sheet 23. These brackets are provided at their upper ends with upwardly facing U-shaped sockets 58, having -cal with-those shown and described in connection with the first form of the invention.
In the operation of this form of the invention,
, the arms so are manually swung forwardly, which turns the rockshaft' 55, and this rock shaft actuates the links '84, which cause the rails 52 to travel upon the rollers 55, The door 54 travels circumferentially and exteriorly with respect to the easing 29 and uncovers th opening 31. The tube 40 is introduced into the sockets El and when the arms 60 are swung rearwardly, the tube passes laterally into the heating shell and also enters the sockets 58 and is held thereby in spaced concentric relation to the heating shell '3 5. The heating shell heats the tube which is plasticized and may be formed or sized.
In Figures 7 to 11 inclusive, I have shown a further modification of the invention. In these figures, a heating unit or furnace 66 is shown, including ends 2 I, corresponding to the ends 2|, and discs 21 corresponding to the discs 21. An outer casing 29' is'provided, corresponding'to the outer casing 23, an inner casing. 30, corresponding to the casing 30 and a tubular heating, sizing or forming shell 35, corresponding somewhat-to the heating shell 35. There is a tubular high frequency coil 34', corresponding to the coil 34,arranged within the space 33. These parts are assembled in the identical manner asdescribed in connection with the first form'of the invention. The ends 2| do not have the radial slots and these ends are closed except for circular openings The discs?! do not'have the radial slots and are closed'except for the central openings 28. The outer casing 29' does not have the longitudinal slot 31 and the inner casing does not have the longitudinal opening-39. These outer and inner casings have continuous periphcries and are openat their ends. The tubular heating shell does not have the opening 39 and its periphery is continuous, while'its'ends are open. The discs 21 have inclined orbeveled faces 61. The-heating shell 35- has a cylindrical bore 38, leading into a taperedportion 69,fiaring outwardly. The heating shell 35'- is formed of carbon, graphite, or the like.
The numeralJEl-designates a formingor 6X- panding mandrel, which is longitudinally tapered, increasing in-diameter outwardly. This mandrel may be formed of carbon or graphite. This mandred is-arranged to enterthe bore of thezheating shell 35', and is smaller in diameter than :the heating shell 35 in diametenendis arranged in spaced concentric relation to the heating: shell. The mandrel i0 is rigidly mounted'uponv a horizontal supporting rod 1 I, mounted within an opening 12 formed in a stationary bracket 13; and clamped in the selected adjusted position'by aset screw 14.
The numeral 15 designates acarriage having a depending portion 15, preferably formed integral therewith. This depending portion has bearings 16, receiving transverse'shafts 11, carrying wheels 18. These wheels are arranged to travelupona stationary track including horizontal. rail 18, havingupstanding guidefianges 80. The ends 2 l 5 are rigidly mounted upon the carriage 15 by brackets 8 I.
Disposed upon opposite sides of the carriage 15 are carriages 82, having bearings 82', receiving transverse shafts 83, carrying wheels 84, traveling upon the horizontal rails 19. Mounted upon these carriages and preferably formed integral therewith are vertical posts 85. Each post 85 is equipped with an adjustable chuck, including a tubular socket 88, formed integral therewith. This tubular socket has a cylindrical bore 81, having a tapered portion 88. Slips 89 are mounted in the cylindrical bore 87 and have tapered portions to engage with the tapered bore portion 88, and these slips are screw threaded, as shown at SI, for engaging a clamping ring 92. These adjustable chucks are adapted for clamping engagement with the tube to be heated, for moving the same longitudinally.
Means are provided to cause the carriages 82 to move longitudinally in unison, comprising an endless sprocket chain 93, passing about sprocket wheels 05, carried by shafts 96, journalled in fixed bearings 97. One shaft 95 is power driven. This sprocket chain is horizontally arranged and its upper run is attached to the carriages 82, as shown at 98. This upper run extends through a horizontal passage 88 formed in the depending portion it and is free from connection with the carriage 15.
Means are provided to shift the heating unit 88 and carriage l longitudinally, comprising a transverse horizontal shaft I 02, journalled in a bearing I03, formed in the depending portion 16. This shaft projects outwardly beyond one side of the carriage and the tracks and is equipped with a hand Wheel I04. The shaft I02 has a pinion rigidly mounted thereon, engaging a stationary rack I88, which is rigidly attached to the ad- J'acent rail 70. By turning the hand wheel I 04, the pinion 105 will travel upon the rack l 06, thereby causing the carriage to be adjusted longitudinally in the desired direction. Any suitable means may be employed to hold the shaft I 02 against improper turning movement.
The operation of the last form of the invention is as follows:
The clamping nuts 92 are unscrewed so that the chucks are expanded. The quartz tube I0! is passed through the right chuck, Figure 7, and its free end introduced into the end of the heating shell 35' and brought into contact with the reduced end of the tapered mandrel, which pro- J'ects in the same for a short distance. The current is turned on and the high frequency coil heats the tubular shell 35' and the mandrel I0 to to a bright heat. The mandrel remains sta tionary and the carriage is stationary during the sizing or forming. The carriage 15 may be longitudinally adjusted with relation to the mandrel to vary the distance between the mandrel 10 and the tapered bore portion 89, to regulate the extent of forming or sizing. This adjustment also brings the mandrel different distances into the heating shell 35 and this has been found to regulate the degree of heat of the furnace, to a certain extent. With the mandrel I0 and heating unit or furnace held stationary, the tube may be manually fed into the right end of the heating shell 5 and through this heating shell and about the mandrel l0 and becomes sized or formed to a larger diameter. The plasticized portion of the tube now passes beyond the left end of the furnace I58 and will freeze and may be brought into the left chuck. The current may be turned off, while the tube is being clamped within the chucks, which is the next step. The heat is again turned on and the two carriages 82 are moved in unison to the left longitudinally of the mandrel. The sizing or forming of the tube about the mandrel is continuous during the travel of these carriages. The carriages 82 push and pull the tube. The operation is continued until the carriage 82 to the right reaches a point near the furnace 82. When this occurs the current is turned off, the heating unit 66 is shifted to the right to uncover the mandrel 18. When the plasticized portion of the tube adjacent to the mandrel T0 freezes, the short right end of the tube may be cracked off, and the formed tube separated from the mandrel.
It is to be understood that the forms of my invention herewith shown and described are to be taken as preferred examples of the same, and that various changes in the shape, size, and arrangement of parts may be resorted to without departing from the spirit of my invention or the scope of the subjoined claims.
Having thus described my invention, what I claim is:
1. Apparatus for heating, forming or sizing quartz tubes or the like, comprising a heating unit, said heating unit comprising a heating shell to be heated by electrical induction, said heating shell having a side opening, a high frequency coil surrounding the heating shell and having a side opening disposed adjacent to the first named side opening, the quartz tube to be heated being passed laterally through the side openings into the heating shell.
2. Apparatus for heating, forming or sizing quartz tubes or the like, comprising a refractory casing including an outer casing, an inner casing, a tubular heating shell arranged within the inner casing, the outer casing, inner casing and tubular shell having side openings in substantial alignment, and a tubular high frequency coil arranged between the outer and inner shells, the tube being moved into the tubular heating shell by a lateral movement of the same.
3. Apparatus for heating, forming or sizing quartz tubes or the like, comprising a refractory casing including outer and inner casings, a tubular heating shell arranged within the inner casing, the outer casing, inner casing and tubular shell having side openings in substantial alignment, a high frequency coil arranged between the outer and inner shells, the tube being moved into the tubular heating shell by a lateral movement, and means to support the tube when introduced into the tubular heating shell.
4. Apparatus for heating, forming and sizing quartz tubes or the like, comprising a heating unit including a refractory housing, said housing comprising ends having openings, discs arranged upon the inner sides of the ends and provided with openings and having outer flanges to enter the openings and inner flanges, an outer casing arranged between the ends and surround ings the discs and held in place thereby, an inner casing arranged between the discs and spaced from the outer casing and engaging the inner flanges and held in place thereby, high frequency coil arranged between the inner and outer casings, a tubular heating shell arranged between the inner flanges and held in place by the inner casing, the outer and inner casings and the heating shell have openings in their sides and the ends and discs having radial openings leading to their first named openings, the tube being moved into the tubular heating shell by a lateral movement.
5. Apparatus'ior heating, forming and sizing quartz tubes or the like, comprising a-refractory housing including ends having openings, discs disposed upon the inner sides of the ends and provided with openings and having outer flanges to enter the openings of the ends andhaving inner flanges, an outer casing arranged between the ends and engaging the discs and held inplace thereby, an inner casing spaced from the outer casing and arranged between the endsand engaging the inner fianges to be held in place thereby, a high frequency coil arranged between the outer and inner casings, a tubular heating shell to be heated by electrical induction arranged within the inner casing between the inner flanges and held in place by the inner casing, and means for introducing the tube into the tubular heating shell.
6. Apparatus for heating, forming and sizing quartz tubes or the like, comprising a refractory housing, said housing having a side opening, a tubular heating shell held within the housin to be heated by electrical induction and having a side opening, a movable door to cover the side opening in the tubular heating shell, and means for supporting the tube when introduced into the tubular heating shell.
7. Apparatus for heating, forming and sizing quartz tubes or the like, comprising a refractory housing having a side opening, a tubular heat ing shell arranged within the refractory housing to be heated by electrical induction and having a side opening, a door to cover the side opening in the tubular heating shell, means to receive the tube and introduce the same into the tubular heating shell through the side openings, and means connecting the door with the first named means so that the door is moved by the first named means,
8. Apparatus for heating, forming and sizing quartz tubes or the like, comprising a refractory housing having a side opening, a tubular electrical heating shell arranged within the housing to be heated by electrical induction and having a side opening, a rock shaft, means mounted upon the rock shaft for holding the tube and passing the same into the heating shell through the side openings, a door to cover the side opening of the tubular heating shell, and operating means connecting the door and rock shaft,
9. Apparatus for heating, forming or sizing quartz tubes or the like, comprising an electricalheating unit including a refractory housing, said housing comprising a periphery and ends, said periphery having a side opening and the ends having radial openings, a tubular heating shell arranged within the housing to be heated by electrical induction and having a side opening, a coil to heat the heating shell, a rock shaft arranged near and upon one side of the housing, arms secured to the rock shaft and arranged near and outwardly of sockets to receive the tube, the sockets being adapted to pass the tube into the tubular heating shell, a cover, and arms carrying the cover and mounted upon the rock shaft.
10. Apparatus for heating, forming or sizing quartz tubes or the he, comprising a refractory housing including a periphery and ends, said periphery having a side opening and the ends having radial openings, a tubular heating'shell arranged-within the housing and having'a side the ends and having opening, a high frequency coil arranged within the housing adjacent to the tubular heating shell, a rock shaft disposed upon one side of the periphery, arms mounted upon the rock shaft and arranged near and upon the outer side of the ends and having sockets to receive the tube and move the same into the tubular heating shell, guide means mounted upon the housing, rails" mounted to travel upon the guide means, a door to cover the side opening in the tubular heating shelland carried by the rails, and operating connecting means between the rails and rock shaft.
11. Apparatus for heating, forming or sizing quartz tubes'or the like, comprising a refractory housing including a periphery and ends, said periphery having a side opening and the ends havingradial openings, a tubular heating shell arranged within the housing and having a side opening, a coil arranged within-the housing adjacent to the tubular heating shell, a rock shaft disposed upon one side of the periphery, arms mounted upon the rockshaft and arranged near and upon the outer-sides of the ends and having sockets to receive the tube and move the same into the tubular heating shell, guide means mounted upon the housing, rails mounted to travel upon the guide means, a door to cover the side opening in the tubular heating shell and carried by the rails, operating connecting means between the rails and rock shaft, and stationary sockets to receive the tube when it is introduced into the tubular heating shell.
12. Apparatus for heating, forming'or sizing quartz tubes or the like, comprising a heating unit including a refractory casing, a tubular heating shell to be heated by electrical induction arranged within the casing-and having a tapered forming bore, the tapered forming bore increasingin diameter toward its outlet end, a tapered forming mandrel to enter the tapered forming bore of the tubular heating shell, the tapered forming mandrel increasing in diameter toward the outlet end of the tapered forming bore and having a reduced end smaller than the normal diameter of the tube and a large end having a greater diameter than such normal bore; a coil arranged adjacent to the tubular heating shell, carriages arranged upon the opposite sides of the heatingunit, means mounted upon the carriages to receive'and hold thetube and move the same longitudinally, and means to move at least one carriage, the arrangement being such that the tapered forming mandrel increases the diameter of the plasticized portion of the tube when the tube is moved longitudinally and presses the outer faced the tube into contact with the tapered forming bore for forming such outer face.
13. Apparatus for heating, forming or sizing quartz'tubes or the like, comprising a heating unit including a refractory casing, a tubular heating shell mounted within the refractory casing and having a tapered forming bore and adapted to be heated by electrical induction, said tapered forming bore increasing in diameter toward its outlet end, a coil arranged adjacent to the tubular heating shell, a tapered forming mandrel toenter the tapered forming bore of th'e' tubular heating shell, the tapered forming mandrel having a reduced end of smaller diameter than the original bore of the tube and 'a large'end of greater diameter than such bore, adjustable means to eifect'a relativelongltudinal movement between the mandrel and tubular heating shell, and means to support the tube and moveable longitudinally of the mandrel, the arrangement being such that the tapered form ing mandrel increases the bore of the plasticized portion of the tube when the tube is moved longitudinally over it and presses the outer face of the tube into contact with the tapered forming bore of the tubular heating shell for forming such outer face.
14. Apparatus for heating, forming or sizing quartz tubes or the like, comprisin a track, a carriage mounted upon the track to move longitudinally thereof, a heating unit mounted upon the carriage and including a refractory housing, a tubular heating shell mounted within the housing and adapted to be heated by electrical induction and having a tapered forming bore which increases in diameter toward its outlet end, a tapered forming mandrel to enter the tapered forming bore of the tubular electrical heating shell, the tapered forming mandrel increasing in diameter toward the outlet end of the tapered forming bore and having a reduced end of smaller diameter than the original bore of the tube and an enlarged portion of a greater diameter than such original bore, means to hold the mandrel stationary, coil disposed in cooperative relation to the tubular heating shell and the mandrel, means to move the carriage longitudinally of the track, carriages mounted upon the track to travel longitudinally thereof and arranged upon the 10 opposite sides of the heating unit, means carried by the last named carriages for receiving and holding the tube, and means to move the carriages, the arrangement being such that the tapered forming mandrel increases the diameter of the bore of the plasticized portion of the tube when the tube is moved longitudinally and also presses the outer face of the tube into contact with the tapered forming bore of the heating shell for thereby forming such outer face.
GUSTAV GUIGAS.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS
US644704A 1946-02-01 1946-02-01 Method of and apparatus for heating, sizing, or forming quartz tubes and profiles Expired - Lifetime US2469597A (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3080606A (en) * 1958-10-27 1963-03-12 Owens Corning Fiberglass Corp Apparatus for curing a cylindrical fiber glass and binder casing
US3280608A (en) * 1959-07-28 1966-10-25 Arthur R Parilla Incremental tube or vessel expander
US20080148778A1 (en) * 2004-03-22 2008-06-26 Hironobu Ueno Curved lamp manufacturing method, curved lamp, and backlight unit

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US1724793A (en) * 1925-01-14 1929-08-13 Thermal Syndicate Ltd Manufacture of fused quartz beams or the like
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US2209739A (en) * 1935-06-08 1940-07-30 Kimble Glass Co Method of shaping tubes
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US1282933A (en) * 1915-12-13 1918-10-29 Le Roy L Pontius Electric oven.
DE339503C (en) * 1919-08-09 1921-07-26 Carl Hardebeck Dr Ing Process for the production of glass tubes with a precisely prescribed internal shape
US1724793A (en) * 1925-01-14 1929-08-13 Thermal Syndicate Ltd Manufacture of fused quartz beams or the like
US1749700A (en) * 1925-12-29 1930-03-04 Fourment Marcel Apparatus for the continuous treatment of metal bodies
US1980875A (en) * 1930-01-01 1934-11-13 Ajax Electrothermic Corp Electric induction furnace
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US3080606A (en) * 1958-10-27 1963-03-12 Owens Corning Fiberglass Corp Apparatus for curing a cylindrical fiber glass and binder casing
US3280608A (en) * 1959-07-28 1966-10-25 Arthur R Parilla Incremental tube or vessel expander
US20080148778A1 (en) * 2004-03-22 2008-06-26 Hironobu Ueno Curved lamp manufacturing method, curved lamp, and backlight unit

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