US1279682A - Heating device for metal-melting crucibles. - Google Patents

Description

G. L. FORT.

HEATING DEVICE FOR METAL MELTING CRUCIBLES.

APPLICATION FILED JULY 18.1911.

LWQQSQJQ PatentedSept. 24,1918.

UNITED STATES PATENT oEEIoE.

GEORGE L. FORT, OF KANSAS CITY, MISSOURI, ASSIGNOR TO FORT-IFIED MANUFAC: TUBING COMPANY, OF KANSAS CITY, MISSOURI.

HEATING DEVICE FOR METAL-MELTING CRUCIBLES.

Specification of Letters Patent.

Patented Sept. 24, 1918.

Application filed July 18, 1917. Serial No. 181,265.

To all whom it may concern:

Be it known that I, GEORGE L. Form, a citizen of the United States, residing at Kansas City, in the county of Jackson and State of Missouri, have invented certain new and useful Improvements in Heating Devices for Metal-Melting Crucibles; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters and figures or" reference marked thereon, which form a part of this specification.

My invention relates to heating devices for metal melting pots such as are used in linotype, and like machines, for supplying molten metal to the type molds, the .principal object of the invention being to provide an electrical device of this character whereby heat may be applied to the crucible and along thedelivery spout so as to readily melt the metal and insure a free flow of metal from the crucible to the molds.

A further object of the invention is to so construct the device that it may be used interchangeably with gas, gasolene or other heaters, such as are ordinarily used with pots of this haracter, without necessitating any change in the usual construction of the crucible.

In accomplishing this object, I have provided improved details of structure, the preferred forms of which are illustrated in the accompanying drawings, wherein:

Figure I'is a transverse vertical section oi a metal melting pot equipped with-a heating device constructed according to the prescomprise an outer casing or jacket 2, having legs 3 at its opposite sides whereby the pot is pivotally supported so that it may be moved by suitable rocker mechanism (not shown) to and from the type mold, to deliver molten metal thereto; the rocker mechanism bein attached to arms 4 which extend rearwar y from near the top of the casing 2.

Located within the outer casing 2, and spaced therefrom, is a crucible 5, having an upwardly and outwardly curved spout or throat 6 extending from its base, provided with a channel 7 which opens from a well 8 in the base of the crucible. The well 8 has ports 9 therein which is fed from the body of the crucible, and is provided with a piston 10 adapted for actuation by a rod 11 to force molten metal from the well outward- 1y through the throat channel 7. I

The space between the crucible 5 and casing 2, except where the heating element is located, is filled with heat resisting packing 12, such as asbestos, and the caslng and crucible are covered by a cap 13 to prevent loss of heat from the crucible and thereby avoid loss in efiiciency of the heating unit employed.

At its base, the casing 2 is provided with an opening 15 through which a heatin device may be inserted into and removed Irom the casing, the device embodying the present invention being so constructed that it may be supported in functional position by the same means that are used to support the ordinary standard gas, or other heating devices.

The crucible here shown is of thetype in general use and atthe lower end is rounded oil to present a maximum amount of heating surface, the spout being exposed on its under side so that it may be heated to retain the metal therein in molten condition until it is delivered into the mold.

In order to secure the best results, the heating device is so made that when it is placed in position it will fit closely about the exposed, rounded end of the crucible and will extend along the 'under side of the throat Gas far as the construction of the casing 2 will permit.

The heating device in its preferred construction, comprises a metallic housing 16,

referably of a cup like character and ha mg an upwardly and outwardly curved trough portion 17 extending from one side; the cup and spout being of such size and shape that they will receive and closely fit about the exposed under surface of the. crucible and spout, so that heat generated by a p H p I I heating unit (presently described) located within the cup and trough portion cannot possibly escape except through the crucible, thereby affording maximum eiiiciency of the heating device.

The housing cup is of such size that when in position it fills the opening 15 in the casing and is provided adjacent its base, with a peripheral flange 18, which seats against the casing, about the opening, to properly locate the heater and prevent any escape of heat through the openin To hold the heating evice in place, the casing 2 is provided, at opposite sides of the opening 15, with downwardly extending, apertured ears 20, adapted for receiving a cross rod 21 which may be extended beneath the base of the cup '16 and through the ears 20-to su port the cup in functional position; the r0 being removable from the ears so that the heater may be removed from the pot. 'In this instance the cross rod and ears constitute the same means employed to support the standard gas or gasolene' burners ordinarily used for heating crucibles of this character.

Located within the housing cup and extending along the trough is a heating unit 23, preferably comprising a series of Wire coils, the terminals of which are extended to binding posts 2425, at an accessible point in 'the base of the housing, and to whichfa're also attached the circuit wires 2627 that lead to a rheostat 28 through which an electric current may be delivered to the heater from wires 29-30.

The heating unit is located at the open side of the housing adjacent the heating faces of the crucible and spout, and in order to prevent the escape of heat through the base of the housing, I partially fill the cup and spout with a layer of heat insulating material 31, which not only serves to prevent the escape of heat, but also supports the heating unit.

Located between the exposed face of the crucible and the coils of the heating unit is a sheet of insulating material 34, shaped to closely fit the rounded end of the crucible and throat and separating the heating coils from the crucible to prevent short circuiting but which is conductive to heat so that the effectiveness of the heating unit is HQI. impaired by its use.

To those familar with linotypes and such metal crucibles, it is known that, due to the intense heat at which the metal is used and the pressure to which it is subjected when delivered to the mold, the metalis sometimes forced; through the pores of the crucible in the form of tiny short threads, which in time constitute a considerable accumulation of metal on the exterior of the crucible, especially at its base below the well, Where the pressure is applied. In order to drain metal accumulating in this manner from the crucible so that it will not effect the usefulness of the heater, I extend a drainage tube 36 through the cup which opens at its upper end into a basin 37 formed by the insulation sheet 34 for receiving the lower end of the crucible; and which, at its lower end, opens to the exterior of the base of the cup.

\Vith this drainage arrangement the metal forced through the crucible into the basin is drained by the tube from the heating device. In order to effectively heat the extreme delivery end of the throat,I provide a tubular heating element operating independently of the crucible heating element, comprising a tube 38 that is located beneath the delivery end of the throat and adapted for support at its opposite ends in the side walls 39 that are extended from the jacket or casing Q to' inclose the throat 6L Inclosed within the tube 38 is a heating coil 40, which is electrically connected,

through the'rheostat 28,with thecircuitwires 29-30 so that heat may be supplied, as in the housing 16, in the egrec desired. The tube is provided along its upper side with a slot 41, so that heat maybe delivered therefrom directlyto the under side of the throat; the slot being closed'by insulation material *3 of the same composition as that of the sheet 34 and the coil insulated from the tube by a casing of insulating material 44.

In using the heating unit, assuming that it is constructed as described, the crucible heater is placed in functional position by inserting the extended "ortion 17 within the opening 15 and beneat the throat 6. The body of the housing is then seated within the opening so that the flange 18 rests against the. base of the jacket and the entire heater is secured in its functional position by inserting the cross rod 21 through the apertured ears 20. The mouth iece heating tube 38 is then placed in its timetional position, and the heating coils of both devices connected through the rheostat to the circuit wires 39-40 Vhen an electric current is closed through the coils the degree of heat delivered therefrom may be regulated by moving the rheostat lovers to the different stations thereon, so that proper heat is supplied to the crucible and in a like manner to the mouthpiece.

It will be seen that by providing separate means of control for the crucible and mouthpiece heating units, the latter may be brought up to' the desired temperature without an excess of temperature in the crucible.-

It is also apparent that as the heating unit is entirely independent of the metal pot, it may be easily removed therefrom if desired so to do, and gas, gasolene, or other heating means inserted and used without alteration of any part of the metal pot or either type of heater, and that the same supporting parts-are employed for supporting both types of heaters.

Having thus described my invention, what Iclaim as new therein and desire to secure by Letters-Patent, is:

1. In a metal pot, a casing having an opening in its lower portion, a crucible located within the casing and provided with a delivery spout, and a heating device removably projectable through the opening in said casing and comprising a body part and extension adapted to lie along the crucible and its delivery spout.

2. In a metal pot, a casing havin an opening in its lower portion, a crucib e located within the casing and rovided with a delivery spout, and a heating device removably projectable through the opening in said casing and comprising a body part and extension adapted to lie along the crucible and its delivery spout and comprising a heating element and a cover of heat conductive insulation.

3. In a metal pot, a crucible having an upwardly curved delivery spout leading from its lower portion, a casing spaced from and inclosing the crucible and its spout and having an opening in its base and an electrical heating device adapted for insertion into and removal from the casing through said opening comprisin a housing having a cupped face adapte for receiving the lower ortion of the, crucible and its spout, a heating element located within the housing and means non-conductive to electricity, disposed between the heating element and the crucible.

4. The combination with a melting pot comprising a melting crucible having an upwardly and outwardly curved delivery spout leading from the base thereof and a casing spaced from and inclosing said crucible and spout having a base opening therein, of an electric heating device comprising a cup like housing, adapted for insertion into and removal from said casing through said base opening and for receiving the lower end of said crucible and having an extended portion curved correspondingly to and closely fitting the said spout, heating coils located within said housing and extended portion, and means for controlling an electric circuit through the coils.

5. The combination with a melting pot comprising a crucible having an upwardly and outwardly curved delivery spout extending from the base thereofand a casing inclosing and insulated from the, crucible and spout, having a base opening therein, of

, an electrical heating device comprising a cup like housing adapted for insertion into and removal from said casing through. said opening and having a flange thereon for seating against the base of said casing about the periphery of said opening; said housing being adapted when in functional position to receive the lower end of the crucible and provided at one side with an extended portion for fitting the under side of said spout, heating coils disposed within the housing body and extended. portion adjacent the crucible parts, insulating material disposed between the housing and coils, and means for controlling an electric circuit through the coils.

6. In a metal pot, a crucible, having a rounded lower end and an upwardly and outwardly curved delivery spout extending therefrom, a casing insulated from the crucible and spout and having a base opening therein, an electrically controlled heating device adapted for application to and removal from the casing through said opening, comprising a cup ike housing having a peripheral flange for seatingagainst the base of said casing about said opening and having an open face adapted to receive the lower end of the crucible and having an extended, trough-like housin at one side extending along and closely iitting said spout, a heating element located witlnn the hous' ing cup, heat conductive means, non-conductive to electricity, interposed between the heating element and crucible and means for controlling an electric circuit through the heating element.

7. In a metal pot comprising a crucible, a heating unit having a cupped portion adapted for receiving a. portion of said crucible and a drainage tube extending from the base' of said cupped portion to the exterior of said unit for the purpose set forth.

8. The combination with a melting pot comprising acrucible having an upwardly and outwardly curved delivery spout lead ing from the base thereof and a casing spaced from and inclosing said crucible and spout having a base opening therein, of an electrical heating device comprising a cup like housing adapted for insertion andre moval from said casing through said base opening and for receiving the lower end of said crucible and having an extended portion curved correspondingly to and closely fitting the said spout, a tubular coil housing located adjacent the mouth of said spout, heating coils located Within the first named housing and extended portion and the tubular housing, and means for separately controlling an electric circuit therethrough.

9. The combination with a meltin pot having a delivery spout, a casin inc osing saidpot and spout, and-means or heating said pot consisting of a heating unit remov ably mounted in said casing adjacent the mouth of said spout; said heating unit comprising a tubular housing having a longiheating element located in the housing adjacent the crucible, a layer of material nonconductive of electricity, interposed between the crucible and heating element, and a drainage tube extending through the cup and said material and opening at its opposite ends adjacent the lower end of the crucible and to the exterior of the cup, for the purpose set forth.

In testimony whereof I afiix my signature.

GEORGE L. FORT.

copies of this patent my be obtained for five cent: each, by eddreuing the "Commiuioner o! ratentl, Wellington, D. 0."

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