US674124A - Electric heater. - Google Patents

Description

No. 674,I24. Patented May l4, mm. c. ROBINSON.

ELECTRIC HEATER.

(Application filed Apr. 17, 1899.)

(No Model.)

IN VENTOH W/ TNE SSE S Tn: mu men ea, mmu'mc" WAINIW. n. c.;

UNITED STATES PATENT OFFICE.

CONWAY ROBINSON, OF BALTIMORE, MARYLAND.

ELECTRIC HEATER.

SPEGIFICATION forming part of Letters Patent No. 674,124, dated May 14, 1901.

Application filed April 17, 1899.

To all whom it may concern.-

Be it known that I, CONWAY ROBINSON, a citizen of the United States, residing at Baltimore city, in the State of Maryland, have invented certain new and useful Improvements in Electric Heaters, of which the following is a specification.

The object of my said invention is to produce an apparatus for heating by means of electricity, especially where high temperatures are required; and it mainly consists of an inclosed electric are formed by means of a carbon or other ordinary electrode and an elec trode formed from metal or other good conductor of heat, the latter being preferably closely joined to or formed integrally with a part or parts by which the heat is to be conducted to the article to be heated in connection with surrounding heat-insulating substances, the whole being contained in a cover or shell of suitable form and material. In this apparatus the metal or heat-conducting electrode should be cup-shaped and inclose the arc and a considerable portion of the end of the carbon electrode in. such manner as to absorb and utilize the heat generated by the arc.

An apparatus embodying said invention will be fully de'scribed,and the novel features sist in the surrounding of an inclosed electric are more or less completely with a good heatconducting materiahprefe'rably copper,which material forms oneof the electrodes of the are, preferably the positive, when a higher efficiency is required. This electrode is closely attached to or formed integrally with a part which is substantially a prolongation thereof, and which is soshaped as to surround or cover more or less completely or lie next to the Serial No. 713,312. (No model.)

piece or pieces to be heated. The whole apparatus is efficiently insulated by covering or surrounding the hot parts by a heat-insulating substance or substances. The covering of the cup in which the arc is formed should be removable, and the whole is contained within a suitable shell. Any desired means may be provided for feeding the movable electrode, either automatically, mechanically, or by hand.

In the drawings the portions marked A represent the outer shell or covering for the apparatus, which may be conveniently and efficiently formed of cast-iron. This is mounted upon a base B, in which I have placed proper resistance-coils C for controlling the electric current and a switch S for throwing the current on and off. In the apparatus shown, which, as above stated, is designed specially for heating solderingirons, there is an opening into one side of the shell A, which in the construction shown has a mouth in the form of an inwardly extending flange (1. Connected to this flange is the part D, by which the heat is immediately conducted to the article to be heated and which in the con-, struction shown is formed integrally with the cup-shaped metal electrode This part D is in the form of a tube and into it the soldering-iron or other article to be heated is inserted when the heating is to be done. It is connected to the flange a by means of suitable bolts d, which bolts, as well as the flange a,are carefully and completely insulated from the part D by insulating material F, interposed between the parts ct and d and surrounding and lying under the heads of the bolts and those portions which would otherwise come in contact with the metal of said flange, so that said part D is completely insulated from the metal of the surrounding shell.

The metal electrode E is preferably, as is clearly shown, of a deep cup shaped formation, the are being formed in the cup and being thus completely surrounded by the highlyconductive metal of this electrode. Resting upon and covering the cup of this electrode is the non-conducting cap or cover .G, through a perforation in the center whereof the carbon Hextends down into the cavity of the part E.- In order that this opening may be more tightly closed than is otherwise practicable, I use the small block g of fireproof material, which neatly fits around the carbon and may slide horizontally over the cap G, so as to prevent the entrance of air into the chamber and at the same time not bind the carbon or prevent it from moving freely. Above the part G, I prefer to place two other corresponding parts G and G and surrounding the whole is, an insulating-cylinder I. These several parts G, g, G, G and I are all preferably formed of fire-clay or similar insulating and heat-resisting substance. Secured above these parts is a metal plate J, which forms the base of the framework for the feed mechanism, and this is insulated from the lower parts by means of the ashestos or other insulating plate K.

Surrounding the carbon H is a soft-iron core L, which is supplied with a gland Z to hold the carbon from slipping through, but

still allow it to be pushed down when required. This core is operated by a solenoid M, operating in a well known manner. Alongside the solenoid are two dash-pots N N, connected by a bar N, which serve, as is well known, to prevent a sudden or jerky motion of the armaturewhen the current is turned on or when the arc is formed. The cylinders of these dash-pots are carried on the tubing T, which in turn is supported by the armature L. The pistons O of the dashpots are carried from asuitable cross-bar on the frame, as shown.

The electric connections will be understood by an examination of Figs. 2 and 4. In operation when the current is turned on the armature L and the carbon H are lifted and an arc is formed between said carbon and the adjacent portion of the wall of the chamber formed in'the cup-shaped metallic electrode. As very little heat can pass the insulatingblocks G, g, G, and G it is practically all abs'orbed by the copper cylinder E and given out therefrom only'through its inside walls, as the outside walls are protected from the loss of heat by the insulating substance F, by which it is kept from contact with the outer shell, and the insulating-packing P, which is inserted in the'outer shell, filling the space between it andthe inner parts, as shown.

The arc being inclosed' prevents loss of heat by air-currents and enables'a longer are to be maintained than would be the case if it were exposed to the air, and for this reason there less resistance in series with the arc, and consequently allows a greater proportion of the .operating feed mechanism therefor, a good heat-conductive electrode having an extension for receiving the article to be heated, means for supporting the same within a surrounding shell, said shell, and heat-insulating material Within said shell and surrounding and insulating said heat conductive electrode, substantially as and for the purposes set'forth.

2. The combination, in an electric heater, of a shell having an opening therein, a'heat conducting and transmitting part secured within said shell near said opening but heatinsulated therefrom, a cup-shaped electrode connected to or forming a part of the same, an ordinary electrode extending into said cupshaped electrode, an automatically-operating feed mechanism therefor, and insulating covering devices covering the chamber formed in said cup-shaped electrode, whereby the heat generated by the electric arc is confined in said chamber and transmitted therefrom through said electrode and its'connected parts, substantially as set forth.

3. The combination, in an electric heater, of an outside shell for mechanical protection having an opening therethrough leading to the working parts of the apparatus, a good heat-conductor adjacentto the opening in said shell and carried therefrom, insulating material interposed between said good heatconductor and said shell, a cup-shaped electrode connected to or formed integrally with said good heat-conductor, an ordinary electrode extending into said cup-shaped electrode, insulating-covers for the chamber formed thereby, and means for operating an electrode to form an electric are, substantially as and for the purposes set forth. J '4'. The combination, in an electric heater, of an outer shell or casing, a heater-body composed of good heat-conductive material'termimating in an electrode and containedwithin said outer shell or casing and supported thereby, heat and electrical insulating material interposed between said heater-bodyand said outer casing where they are united, a removable electrode the inner end whereof approaches the electrode carried by the heater-'- b'ody, automatical-ly-operating means for operating thesame', suitable heat and electrical insulating material surrounding said lastnamedelectrode and covering the chamber in which the arc is formed, and suitable electrical connections connecting said electrodes, said heater b'ody being hollow and adapted to receive the article or material to be heated. 5. The combination, in an electrical heater, of an outershell or casing having openings in its top and side, a suitable base therefor, a heater-body terminating in a cup-shaped electrode and supported from said outer shell or casing adjacent to the opening therein, insulating material interposed in the joint between the heater-body and the shell or casing, a cylindrical part extending upwardly from the heater-body to the'upper opening in the shell or casing, perforated caps composed of refractory and insulating material occupying the upper portion of said cylinder, an electrode perpendicularly positioned and extending down through. the perforations in said caps, an electrical connection extending to said electrode, means for operating said elec trode to form the arc, and an electrical connection extending to the lower cup-shaped electrode, said last-named connection having resistance interposed therein, said heaterbody being hollow to receive the article to be heated, substantially as shown and described.

6. In an electric heater, the combination of a heater-body, a shell or casing surrounding the same with an opening extending through the shell or casing to the inside of the heaterbody, said heater-body supported from the shell or casing near said opening but electrically and heat insulated therefrom, electrical and heat insulating material surrounding the heater-body between the heater-body and the outside shell or casing, an electrode adj ustable toward and from said heater-body to form an arc the hotter portion of which is partly surrounded by the heater-body, an automatically-operating feed mechanism therefor, a cylinder-of insulating and refractory material extending through the insulating substance inside the shell or casing and giving access to the electrode portion of the heaterbody, and insulating and refractory pieces covering said electrode portion and located inside of the cylinder.

7. The combination, in an electric heater, of a metallic heater-body forming a good heatconducting electrode and having a chamber therein adapted to receive the article to be heated through an appropriate opening, another electrode mounted to be movable toward and from the heater-body electrode, insulating material surrounding said heaterbody electrode provided with an opening for the entrance ofsaid movable electrode, suitable electrical connections with said two electrodes, and means for operatingsaid movable electrode to form an are, substantially as set forth.

8. The combination, in an electric heater, of an outside shell having an opening therein leading to the working parts of the apparatus, a good heat-conductor arranged Within said shell adjacent to the opening therein and carried therefrom,insulating material interposed between said good heat-conductor and said shell, a good heat-conductive electrode connected to or formed integrally with said heats conductor,"an ordinary electrode extending into proximity with said good heat-conduct ive electrode, and means for operating said electrode to form an electric arc.

In witness whereof I have hereunto set my hand and seal, at Indianapolis, Indiana, this 25th day of March, A. D. 1899.

CONWAY ROBINSON. [L. s.]

Witnesses:

JAMES A. WALSH, v C. S. FRYE.

Images