US1714578A - Electric heating apparatus - Google Patents

Description

May 28,` 1929. y P. F. wElss ELECTRIC HEATING APPARATUS Filed April zo, 1926 Ofwel;

Patented May 28, 1929.

UNITED STATES,.-l PATENT OFFICE.y

PAUL l'. wmss, or CHICAGO, ILLINOIS, AssiGNoa' or' ONEsHALF lro HAROLD J. PETER- sON, or CHICAGO, ILLINOIS.

ELECTRIC HEATING `APPARATUS.

Application led April 30,

The present invention relates to electric heating. apparatus and has particular reference to that type of heating apparatus wherein the heat is generated within a body of li uid` by passing the electric current theret rough. Y

One of the principal objects of tlieinvention is to provide an improved construction of radiator for household heating eniploying this geneialprinciple of operation. The advantages of this 'method of heating a building, room or other premises are manifest. For example7 this method of heating dispenses entirely with boilers, furnaces, fuels, piping and all of the objections incident thereto'. One of-these heating radiators can be placed in each room or other area to be heated and the current necessary for the Operation of these heaters can be derived from the ordinary electric lighting circuit,

or from a separate power circuit having lower rates for large electrical consumption. vWhile the advantages of'household heating by electricity have long been recognized apparatus heretofore available for this purpose has been subject to 4numerous objections.

One of the principal objections to this type of apparatus, as heretofore construct- 3o ed, has been the comparatively short life of the resistance .element in which the electrical energy is converted into heat. Furthermore, such resistance elements have a ver small area` of heat radiating surface and consequently have to operate with a very intense heat .concentrated in the immediate result that such devices are likely to' burn objects placed near them. Obviously, with 40 all ofthe heat required for heating a-room emanating from a localized point there is no uniformity of distribution of the heat with this type of heating apparatus. They vare also subject to the objection that they have no reserve capacity forstoring up heat for .later dissipation into the room after the current has been turned Oii". I have avoided all of these objections in the present radiator construction by first converting the electrical 5o energy into heat within a liquid which is contained in the radiator and which serves as the resistance medium; and then dissipating vthe heat thus generated by radiation 1926. Serial No. 105,773.

from the relative large surface area of the radiator.

One of the more specificobjects of the invention is to provide an improved manner ing-.the'area of contact between the liquid and one/of these electrodes.' This feature of my invention has application to all types the resistance medium. For example, the invention maybe utilized for heating glue pots and other similar devices where a uniforri, closely regulated temperature is desire of 'heating apparatus utilizing a liquid as Another Object of the invention is to pro- I vide a construction of radiator of like heating device of this general nature in which the outer shell or casing is insulated from both sides of the circuit vso that there is no possibility of its becoming grounded or causing a shock when touched.

Other Objects and advantages inherent in my invention will appear from the'following description ofl a preferred embodiment thereof.

In the drawing illustrating this embodi ment: c

Figure 1 is a vertical sectional view through a radiator, such as might be employed for hpusehold heating; and proximity Of the heating resistance with the Fig. 2 is a similar view through a modiied construction.

Referring first to the adaptation shown in Fig. 1, the radiator comprises any desired form of outer Casing 8 constructed either as a casting Or of sheet metal, and having any suitable supporting feet 9. In the construction shown, the radiator is made of sheet metal, the side and bottom walls 11 and 12 thereof being formed from a single sheet or separately, y as desired. The top of this casing-is closed by a top late 14 which is bolted or Otherwise secure to the marginal ange 15 extending from the upper edges of the side walls 11.

Supported in the lower part of this main or outer casing is a Chamber Or pan 17 which i' to ground the outer casing.

contains the conducting liquid 18 and which is insulated from the outer casing. The corners and bottom of this inner container may be insulated from the outereasing by the intel-position of insulating spacers 19 and 21 between the two. The upper yedge of this inner container is joined to the side walls ,of the outer casing b v anvsuitahle construction of insulating seal. For example, a

slotted bead 22 of insulating material may be p esscd down over the upper edge of' this linner container, with the outer side of this f inafter appear, this inner container is connected to one side of the electrical circuit 4and constitutes the stationary electrode for passing the electrical current through its contained liquid 18. By thus insulating` this inner container from the outer casing in the manner hereinbefore described, the cha'nce of grounding that vmight occur would be through a path of such high resistance that it would be of no consequence.

The liquid in the inner container is maintained at a substantially definite level, at approximately the point indicated, and dipping into this liquid is a movable electrode 28 tiltably suspended, preferably at one end thereof, from a stationary bracket or hanger 29 which is secured to the top plate 14 of the outencasing. This bracket or hanger is insulated from the movable electrode in any suitable manner, as by interposing .a'relatively long insulator 31l in the length of thehanger. The lower end of the insulator or hanger is hinged or pivoted to the movable electrode; for example by a Z-shaped sheet metal strap 32 which will have ample flexure to permit the limited v tilting movement of the electrode.

The movable electrode extends through a conslderable part of the length o f the inner container, and is so arranged with respect thereto that the shortest path of conductivity between the movable electrode and the inner container or stationary electrode 17 1s 1n a direction downwardly through the liquid to the bot-tom wall of the container or electrode 17, whereby the major portion of the current flow will=be through this path of least resistance. Hence, it will be seen .that raising and lowering the movable electrode 28 lthe`spacing `between different portions of the two electrodes will vary in this path and the resistance will be increased sylphon.

or diminished. At any preferred point, preferably intermediate its-ends, this movable electrode has operative connection with a control rod 34. The electrode is insulated l from the control rod by the interposition ofan insulator 35 between the two. The lower end of the insulator is secured to the movable electrode by a thin sheet metal strap section 436, similar to the strap section 32. The control rod 34 has a swiveled connection 37 with the upper end of the insulator, whereby the control rod can be rotated relatively to the insulator.

The control rod has operative connection at its upper end with a pressure responsive element 38. This pressure responsive element may consist of a diaphragm, a bellows,

or a sylphon, one side of which is subjected to the pressure within the casing and the other. side ofwhich is acted on by atmospheric pressure. In the preferred construction shown, this pressure responsive element is of that type commonly known as a sylphon, the latter having its lower end Aopen so that the interior thereof willfbe subjected to the pressures generated within the casing.

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a threaded boss 44 formed in the /top plate 45 which closes the top of the sylphon B8. The upper end of this control rod is provided with a knob 46 by which the rod can be screwed up and down in the boss 44 to adjust the height of the'movable electrode relative to the upper end of the sylphon, or relative to the level of the liquid 18. i

A compression spring 47 bears at its lower end against the end plate 45 of the sylphon. The upper end of this spring bears against a ring 48 which screws into ,anA internal thread formed in the upper end of the shell 41. This ringis formed` with a flange or any other form of gripping means by which it can be grasped for screwing the ring up or down in the shell and thereby varying the pressure of the spring 47. y

It will be seen that the above construction providestwo adjustments,`one for varying the effective length of the control rod 34 and the other for adjusting the normal spring pressure impressed on the upper end of the Both of theseV adjustments are readily accessible by raising the hinged cover 42. `By adjusting the effective length of the v control rod 34, the area of the movable electrode in contact with the liquid 18 can be adjusted for any given pressure and temspring 47, the maximum pressure and temlight circuit or with a powercircuit through j lower part of the outer casing. Where such I perature which the radiator will normally tend to maintain can be adjusted to any desired point.

The shell 41 is dropped ghrough an opening in the cover plate 14 and has a flange 51 which is 'bolted-to the cover plate around this opening. The electrical connections are established through a socket 52 which is secured to this flange 51 and which a longl insulating portion 52 extending down through an opening 53 in the cover plate 14. The two conductors 54 and 55 extend' down from this insulatin portion 52 and establish connection with t e inner-container 17 and with the movable electrode 28, the flexibility of the conductor 55 permitting the controlling movement ot' the movable electrode. Insulating sheathing 56 is'provided on the'upper portions ofi these conductors. Electrical connection may be made with the the outer conducting lead 57 and a conventional terminal plug 58 receivable in the socket 52. 'f

A vent plug 59 is provided to close a ventin the top plate ofthe outer casing. The

or throng ra filling inlet 61 entering the filling inlet is employed, it is located substantlally coincident with the desired liquid level in the inner container so that in vcharg- `1ng the radiator the liquid can only be brought up to this level. -This inlet consists of an elbow section having its inner end joined to the container 17 and its outer end extended upwardly and threaded `for receiving a closure plug 62:5 An insulating bushing 63 insulates this filling inlet from the outer casing where it passes through the casing. y l

A rain cock 65 may also be provided for draining the inner container 17. The upper Cil end of this drain cock is joined to the container and the cock extends through an `in sulating bushing 66 in passing down through the outer casing.

In the operation of the device the eilective length of the control rod 34 and the pressure of the spring 47 are preferably so adjusted that with the radiator cold the movable electrodewill bev immersed to a` sufiicient depth to insure a relatively large current low'whenthedevice is started into operation so that t-he liquid will heat up' quickly. As the liquid rises in temperature, the confined volume 'of air or gas in the upper part of the radiator will absorb some of the heat and expand, thereby acting on the sylphon to raise the movable electrode slightly and reduce the `current flow. Asv

son'as the liquid begins to boillthe steam `radiator' is to be maintained.

pressure in the upper part of the container', wh1ch pressure 1s employed as the regulating factor for controlling the working tempera-L By constructing the To ture of the radiator. electrode 28 with a relatively extensive arca, as shown, 'a lnicely graduated controlling action can be obtained, the sylphon holding the movablcelectrode in a position corresponding to a current flow commensurate with the. desired temperature at which the In constructing the movable electrode 28 to have a relatively large surface area for contact with the liquid 18, two or more. spaced plates 67 and 68 may be joined together by bolts er rivets 69 assing through spacing sleeves which hold)- the plates in spaced relation.

.The modification illustrated in Fig. 2 dif fers principally from the preceding embodiment in the Vparticular form of the casing and in the form of the movable electrode. In this embodiment the casing 70 is constructed of two concentric cylindrical shells 71 and 72 which define a chamber annular in form at the lower part of the casing.

The top of this chamber is closed by a cirloo the ends of a multiple arm spiderf7 8. The J annular electrode members 76 are supported in spaced relation on the rods 77 ,by interposed washers 79.

The spider 78 is suspended through an insulator 35 from a control sylphon which is disposed centrally of the casing. This control sylphon is a substantial duplicate'of the sylphon just described, and accordingly I have not illustrated the' same in detail. It will have a similar adjustable spring 47 and adjustable 'connectionbetu'een the control rod 34 and the upper end of the sylphon,.for affording the two adjustments previously described. The electrical connections to the movable electrode and to the main casing 70 will be evident from the preceding description.

In many instances therewill be no objec- .tion to the outer casing of the device being live7 or grounded. However, where this is objectionable, the easing 70 may be. completely enclosed by an ovuter erforated cage las or screen 81 which is insu ated from thev main casing. j The top of such cage or screen' may be insulated from the main casing by an insulating ring 82 which engages down 'over the joining fianges 71 and 73 of the casing.

The lower edge of this screen is insulated from Vthe casing by insulating blocks 83 secured between the two. This screen has a inultlplicity of apertures or slots 84 therein through w ich air` can circulate for contact with the main casing. This screen can be readily removed for affording access to the control adjustments. It will be noted that the lower annular wall 72 increases the hcat radiating surface of the casing.

In each of the preceding constructions the movable electrode, together with the metallic wall whichv constitutes the stationary electrode, will both be constructed of a metal or metalsbetween which there Will be no plating action. 'For the conducting liquid ordinary water will suiice, although I also contemplate the use of certain other conducting liquids, which in their electrolysis, will not liberate any obnoxious or dangerous' liquid therein, a movable electrode adapted to have a portion thereof immersed in said liquid for' establishing a conducting path through said liquid between said electrodes, and control means operating upon said movable electrode for controlling thel temperal ture of said radiator.

container being a paratus, the combination of a container comprising a stationay electrode portion, said aptedto contain a conducting liquid therein, a movable electrode adapted to have a portion thereof immersed in said liquid for establishing a conducting path through said liquid between said electrodes, and control meansA for varying the area of contact between said movable electrode and said liquid.

f 4. VYIn electrically operated heating apvuparatus', the combination of'a container comprising a stationary electrode portion, said container being adapted to contain a conducting liquid therein, a movable electrode adaptcd to have aportion thereof immersed in said liquid for establishing a conducting path through said liquid between said electrode, and pressure responsive means operating to control said heating apparatus by changing the position of said movable electrode relative to said liquid. x

5. yIn electrically operated heating apparatus, the combination of a container comprising a stationary electrode portion, said container' being adapted to contain a conducting liquid therein, a movable electrode adapted to have a portion thereof immersed in said liquid for establishing a conducting path through said liquid between said electrodes, and a pressure responsive element for raising and lowering said movable electrode rela-tive to the liquid level in said container. 6. In electrically operated heating apparatus, the combination of a container comprising a stationary electrode portion, said container being adapted to contain a conducting liquid therein, a movable electrode adapted to have a portion ithereof immersed in said liquid for establishing a conducting path through said liquid between said electrodes, pressure responsive means for moving said movable electrode in said liquidto vary vthe current flow through said liquid, and

means for adjusting the responsiveness of said pressure responsive element to different pressures.

7 In electrically operated heating apparatus, the combination of a container comprising a stationary electrode portion, said container being adapted'to contain a .conducting liquid therein, a movable electrode adapted to have a portion thereof immersed in said liquid for establishing a conducting path through said liquid between said electrodes, a pressure responsive element, an operating connection between said movableI electrode and said pressure responsive element, and means for varying the effective length of said operating'connection.

8. In electrically operated heating appa- 'ratus, thecombination of acontainer comprising a stationary electrode portion, said container being adapted to contain a conduct-ing liquid therein, a movable electrode adapted to have a portion thereof immersed in said liquid for Vestablishing a conducting path through said liquid between said electrodes, a ressure responsive element subjected to tlie pressures generated within said container, an operating connectionbetween said ressure responsive element` and said movable electrode, and means for adjusting the immersion ofsaid movable electrode in said liquid for a predetermined condition of said pressure responsive means.

9. electrically operated heating apparatus, the combination-of a container compath through said liquid between said eleetrodes, and means for insulating said electrodes and the conducting liquid from the outer surface of the device.

10. In an electrically operated radiator, the combination of a casing comprising a stationary electrode portion, said casing being adapted to contain a conducting liquid, a movable electrode partially immersed in said liquid, a supporting bracket extending between said casing and said movable electrode for tiltably supporting said electrode,

a sylplion supported by said casing With one side subjected to atmosphere and the other side subjected to the pressures generated within said casing, and operating member connecting said movable electrode with said sylphon, a spring resisting flexure of said sylphon under the pressures generated Within said casing, and means for adjusting the position of said movable electrode relative to a predetern'iined pressure within said casing. n

11. In an electrically operated radiator, the combination of a casing comprising a stationary electrode portion, saidcasing .being adapted to contain a conducting liquid, a movable electrode adapted to have a p0rtion thereof immersed in said liquid for establishinv a conducting path therethrough between said electrodes, a sylplion mounted in said casing Vhaving one side subjected to the pressures generated within said casing, a motion transmitting connection between said sylphon and said movable electrode, a

spring reacting against said sylplion, means for adjusting. said motion transmitting connection, and means for adjusting said spring.

12. In electrically operated heating apparatus, the combination of a main casing, an inner container -insulated from said main casing and adapted to contain a conducting liquid, and' electrode nieans having contact with said liquid for establishing a current iiow through said liquid.

13. In electrically operated heating apparatus, the combination of a main casing, an inner container insulated from said main casing and adapted to contain a conducting liquid, said inner container 'constituting one electrode, and a second electrode having a portion thereof immersed in said liquid for establishing a conducting path therethrough.

14. In electrically operated heating apparatus, the combination ot' a casing comprising a stationary electrode portion, said casing being adapted' to contain a conducting liquid, a second electrode adapted to have a portion thereof immersed in said liquid for establishinv a conducting ath through said liquid, and a screen over insulated therefrom.

15. In an electrically operated household heater, the combination of a casing, an inner container electrically insulated from 'said casing and adapted to contain a conducting liquid, electrode means having contact Withsaid liquid for establishing a current flow through the liquid, and automatic control means for regulating the working temperatures of said heater by efecting movement of said electrode means within said container, A

PAUL F. WEISS.

said casing and

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