US1420693A - Electric boiler - Google Patents

Description

H. E. COHEN.

ELECTRIC BOILER.

APPLICATION HLED MAR. 4, 192'2.

Pan'a June 27, 1922.

2 SHEETS-SHEET 1.

HI Ill' 66 /NVENTo/e A TTORNEYS H. E. COHEN.

ELECTRIC BOILER.

APPLICATION HLED MAR. 4, 1922.

Patented June 27, 1922.

2 SHEETS-SHEET 2.

w' A Trak/v5 Ys UNITED s'rATEs PATENT OFFICE.

HYMAN E. COHEN; OF SYRACUSE, NEW YORK.

ELECTRIC BOILER.

Specification of Letters Patent.

Patented June 27, 1922.

Application fiied March 4, 1922. serial No. 540,968.

generator disclosed in my copending ap? plication Serial. Number J;1(3,899, filed October 12, 1920; and has special reference to the provision of a boiler of this nature which may be operated witli a maximum of surety, safety and facility.

In the steam generator forming the subject matter of my above mentioned copending application one or more electrical heating elements in the form of resistance tubes is or are arranged in a boiler and disposed y therein with an end or the ends of the tube 'or tubesl exposed above the water level, the

said tubes when electrically heated, as by passing a current therethrough, etfecting the segregation of water within the tube, the heating of the said segregated water and the expulsion of the same from the top end 'of the tube in the form of generated steam. These tubes in one form of my invention are arranged to be fioated in the boiler for following the changing liquid level therein to the end of maintaining the upper ends of the tubes exposed above the water level a Constant predetermined amount. A prime desideratum of my present inventioii comprehends the provision of a boiler` construction in which the electrical resistance tubes are floated in a 'nanner to render the operation of the sanie in practice safe, dependable and secure.

I have found after considerable experimentation that in order to obtain an eflicient floating construction in the steam boiler, which is usually subjected to considerable pressure during steam generation, that such factors as the character of the fioat, the mounting of the float and movement of the same in the boiler casing are considerations of prime importance. It is very desirable, for example, that the fioat be freely movablle in the boiler casing without let or hindrance so that the rise and fall of the fioat may be assured during changeslin the liquid level of the boiler. Moreover, the construction of the float should be such as to withstand the heavy pressure to which it is subjected in practice. Furthermore, the electrical resistance elements must be so mounted o n the float and associated With the boiler casing as to prevent the samel from making contact with the boiler casing to minimize grounding troubles and' also to prevent the same from moving transversely in the casing to reduce the liability or tendencyof grounding or largely modifying the .resistance between the said electrical heating elements-and the boiler casing. A principal object of the present invention therefore compreheiids the provision of a construction 'in which the float and the tubular elements thereon are efliciently supported within the casing and movable there- 1n to prevent undesirable binding and jamniing of the parts and .to permit the free rise and fall of the float with the construction such as to minimize or .prevent any grounding tendency of the electrical heatmg elements.

Another important desideratum of my present invention comprehends a construction of th'e type referred to in which the electrical elements are protected against burn outs and in which needlessconsumption of energy is prevented when the water in tlhe boiler falls'below .a ipredetermined eve I have found it hglily desirable where an absolutely safe and dependable boiler is desired to provide au automatic cut-out means operable by movement of the float in the boiler, the construction and arrangement bemg such that when the tloat following the water level falls below a predetermined height, the Circuit to the electrical heating elements is opened or cut out to prevent the wastage of current and to prevent the burning out of' the electrical heating elements.

Atfurther principal object 'of the invention tliei'efore comprehends the provision of a cutout means of this nature which is eflicieutly associated in a simple manner with the floating apparatus.

To tlie accomplishment of the foregoing and such other objects as may hereinafter appear, myinvention consists in the eleinents andtheir relation one to the other, as hereinafter particularly describedl and sought to be defined in the claims, reference being had to boiler showing the fioating equipmenttherein, and

F igu're 2 .is a perspective and diagrammatic view thereof showing, the floating equipment removed from the boiler casing and the control circuits therefor.

Referring now more in detail to the drawings, the electric boiler of my invention com'- prises the preferably cylindrical casing or shelly10,lthe said casing being provided With the closure 11 adapted to be attached to the casing structure as bytbeing bolted to a top flange 12 of the boiler casing as by means' of the spacedly arranged bolts 13, the suitable gasket 14 being interposed between the closure and the 4casing flange for obtaining an effective seal between these parts. Connected to the bottom of the casing Shell 10 there is provided thewater inlet piping 15 and connected' to lthe side wall of the boiler casing 10 adjacent its top there is provided the steam outlet piping ,16. The boiler may be further providedwith the usual water gauge 17' and the pressure gauge 18'. The casing.

or Shell 10 is intended for the recept-ionof a suitable supply of water and for. heating this water for steam generation I provide a plurality of electrical .resistance elements in the form of carbon tubes, as disclosed in m above mentioned copending application, 'the said carbon tubes functioning to segregate' portions of the water in the boiler'shell and to heat the same substantially instantly for generation of steam. The resistance tubes preferably comprise a plurality of tubular elements 17 .arranged in series and connected by means'of a plurality of connectors .18, these tubular elements being connected to any source of electrical supply, one end of the series of tubes being. to this end electrically connected by means of a conductor 19,

to a binding post 20 attached to the boiler closure 11l and suitably insulated there-from, the other terminal of the series of tubes 17 being connected by ;means of a conductor 21 to a second bindin post 22. carried by the boiler closure' 11 an suitably insulated thereo from, thebindingposts 20 and 22 being intended for connection to a suitable source of supply, as wil'be made clearer hereinafter. Upon ener ization or closing of the circuit to the heating units 17 ,the water segregated.

thereby is instantly heated and transformed into steam which issues from the top ends of the tubes in a continuous lfountain formation. The tubes 17 are preferablyarranged within the boiler casing with the top ends thereof exposed above the Water level 'to the 'end of 'efecting efficient steam generation,'

and `where a Constant characteristic of steam is desired, it ispreferred-to' maintain the exposed ends of the tubes in constant a'nd predetermined relation With respect to the water level and for this purpose these tubes are floated within the boiler to follow the changing liquid level therein.f y

- As heretofore stated, a rincipal object of my present inventionre ates to' the. provision of a boiler 'construction' in which the fioated heating elements-are arra' ed "and mounted for eflicie'nt movement an 'operation in the boiler, the floatingl equipment being adapted to rise and fall with the 'changing. liquid level with facility and surety. F or the purpose of withstanding the high pressures attainable in -the boiler during steam generation I have found it very 'desirable to provide the hollow substantially ball. shaped metallic float 23 and lto the float I attach the resistance elements 17, thelatter being preferably arranged circumferentially or peripherally on the said float. A' very convenient means of attaching the resistance elements to the float comprises the provision of a resilient and insulating sheath such as a rubber covering 24 stretched over the flattenedside walls 25 of the float, the series of y semi-cifrcular sections hinged together by means-of' the hinging element` 27, the other ends of these semi-circular Sections being adapted to be drawn together by means of a clamp 28, the provision of this means elffecting' a secure attachment of the tubes 17 on the float 23. For obtaining 'a float which will readily respond and rise andfall with the changing liquid level in theboiler while minimizing grounding tendencies, I have found it very suitable to provide a rectilinear guiding means for the float, the guiding -means conveniently comprising a preferably vhollow stem 29 carried by the boiler closure 11 as by' being threadedly received by 'a plug 30 which in turn is threadedly attached to the boiler closure-11 as at 31, the said hollow stem 29 slidably receiving the float 23 and the` heating elements carried thereby, the said float 23 beingl referably provided with a centraljjsleeve-liie integral portion 32 of a diameter to'be freely received by the hollow -stem 29. vThe Stein 29 is preferably arrangedV centrally of the cylindrical shell 10 andthe float and its attached resistance tubes are thus preferably movable centrally 'of .the boiler. 'With theprovision o f this construction the floatingequipment is efficiently ided for movement within the boiler casing for obtaining a dependable operation thereof'.

' For the urpose of obtaining a safe and fool-proc i construction to prevent' the needless consumption of energy and to prevent the burning out of the heatin'g elements When thie Water in the boiler is or falls below a predetermined level, I have found it desirable to provide means for controlling the energiz'ation of the Circuit to the heating elements depending upon the position of the floating equipment in the boiler. Referring now toFigure 2 of the drawingsl, the Circuit totheheating elements may.l comprise the Conductors 33 and34 'Connecting the binding posts and 22 through fuses 35 and 36, if desired, to a main control switch 37, the conductor 33 being connected through the i bar 38 of' the'said switch to line 39 leading to a source of supply, the conducior 34' being connected through the other bar 40 of the switch to the other line 41 leading to the source of supply. The switch 37 is normally maintained in open position and to this end this switch is spring Controlled, a .spring 42 being provided anchored to the transverse insulating bar 43 of the switch 37 for maintaining' the said 'switch in the normaliy open position as indicated in full lines in figure 2 of the -drawings F or controlling the Circuit to the heating elements, the switch 37 is controlled so that operability of the said switch is prevented under the ab-' normal boilerconditions presented when the liquid therein falls .below a predetermined' level., I f

For controlling the V'switch 37 to control the Operability thereof, there is preferably provided a second Circuit Controlled by the v'movement andthe position of the fioating equi ment within the1b oi1er. Still referring to igure 2, this circult includes a solenoid or electro-magnet 44, one terminal of which is connected to the conductor ,34 by means of the conductor 45, the other terminal of which is connected by means of a conductor 46 to a third bindingpost 47 carried by the boiler closure. 11 and suitably insulated therefrom, the binding post 47 being in turn connected to a vcutout switch generally designated as 48 adapted for cooperative association with the binding post 20, as will be described' presently, for closing the Circuit.

to the cond-uctor 33. A This Circuit including the-solenoid 44 is therefore arranged in parallel 'with' thevheating elements acrossthe ; lines 33 and 34, energlzation or deenergization of the solenoid 44 lbeing therefore under .the control of the main switch 37. The solenoid 44` is arranged for Operating an larmatui'e looking element 49, the latter being pivotally mounted as at 50 and normally urged to inoperative position by means of a i lspringl anchored the-reto. The armature 49 may be suitably notchedas at 52 to cooperate with a. lockin pin or st'ud 53- formiing. part .of or attac ed to the switch 37.

ytion for unlocking the switch 37 and the .ment with a stationary contact arm 55, the

With the provision of this construction it will be evident that upon enel'gization of electro-magnet or solenoid 44 the armature looking element`49 will be moved to Cooperate with the locking stud 53 for the purpose of looking the switch 37 in closed position in the event that the said switch is moved to the said closed position, -the switch being maintained in closed position during continued energization of the magnet' 44. It will be further apparent that in the operation of the boiler, if the magnet 44 is de-l ene'rgized, the lock armature 49 `will be' moved by the spring 51 to inoperative posispring 42 will move the said switch 37 to open position for opening the circuit to the heating elements..` v

For efiiecting the desired'controi of the armature 49 by the electro-magnet 44, the. cut-out switch generally designated as'48 hereinbefore mentioned is provided. The switch 48 comprises a movable switch orfcontact arm 54 movable into and out of engagemovable arm 54 being rockabiy mounted about a pivot 56 provided in an upstanding bearing 57 formed preferabiy integrally with a bracket 58, which is connected mechanically and electrically to the binding. post 47, the stationary contact arm.55 being in turn attached 'for electrical connection to the binding post 20. For movin'g'the contact arm 54 into andout of operative engagement with the contact arm 5'5 there is provided a rod 59 slidably movable in` an apertured boss 60 forming part of the bracket 58 and connecting the rod 59 and the switch arm 54 there is provided a tension spring 61, one end ofv which is anchored to the end of. the arm 54, the other end of which is anchored to the rod 59, as will be Clear from a consideration of Figures 1 and 2 of the drawings. The rod 59 is adapted for sliding movement in the boss'bearing 60 and .V110

when the rod is moved to its uppermost position the spring 61 will exert tension upon the arm 54 for moving the same intothe contacting position as shown in Figure 1 of the drawings. When the rod 56 is moved to descended position as indicated in dotted lines in Figure 1 and as shown in Figure' 2 of the drawings, the spring 61 exerts tension upon the arm 54 for snapping the Same' out of contacting position, thus opening the circuit to the electro-magnet 44. The position, therefore, of the rod 59 controls the operability of the magnet 4-4 and therefore the operability of the main switch 37.

within the hollow stem 29, an insulating rod or bar 63 being provided for connecting the rod 59 to the rod 62, one end of the bar 63 being adjustably attached to the rod l59 as by means of the adj ustable looking nuts 64, the other 'end of the insulating bar 63 being attached to the rod 62 as by receiving an outwardly turned portion G5 thereof. The rod 62 is provided at its bottoni end with a stop disk 66 which may be adjusted on the rod 62 by means of the adjustable lock nuts 67, the adjustment being provided for varying the region in which the cut-out switch S is to be operated by the fioating equipment. With the provision of this construction it will be seen that as the fioating equipment descends with the Afall in the liquid level the bottom portion of the fioat 23 when the fioat reaches the position as indicated in dotted lines in Figure 1 of the drawings, will engage the 'stop disk 66 and will move the rod 62 in the hollow stem 9:9, a suitable slot 68 being provided in the side wall ofthc stem for permitting this motion, movement of the rod '82 effecting, aswill be ohvious, the descent of the rod 59 and the movement of the switch arm 54 to open position as indicated in dotted lines in Figure 1. ith the parts arranged in this manner the switch will be automatically opened and'when the switch 37 is manually closed the said switch will not be maintained closed under this abnormal boiler condition. lt will be further apparent that when a supply of water is admitted to the boiler casing 10 the i'ioating equipment will rise to the position shown in Figure 1 of the drawings, and in rising to the desired level the upper portion of the float 23 will enga'ge the insulating bar 63 for moving the contact arm 54; to close the circuit Controlled thereby. When the tank orboiler shell is thus filled to the desired height, the electro-magnet 4a is conditioned ,for energization when the switch 37 is closed, the lo'cking means for the said switch being thus rendered operable. The stop disk 66, besides functionlng for being engaged by the fioat 23 for Operating the switch 48, also functions as a stop element to prevent movement of the fioat 23 from the stem 29, this construction providing the attachment oflthe complete float-ing equipment and the cut-out switch to the boiler closure 11, removal of the boiler closure as shown in Figure 2 of thel drawings being effective for removing the entire floating equipment and associated parts for purposes of inspection or I'epalr.

The operation and use of Iny electric boiler will, in the main, be apparent from the above detailed description thereof.. It. will. be apparent that when the boiler is suitably supplied with water to the desired height, the main control switch 37 when manually closed Will be maintained closed for connecting the. heating tubes `17 to a source of current supply, heating of thetubes etfecting the generation of`steam in the chamber above the water supply, the steam moving through the Outlet 16 for use in other apparatus. As the liquid supply becomes exhausted the ioating tubes 17 move downwardly in the boiler casing suitably guided to obtain facile operation and to eliminate grounding tendencies, a predetermined amount of the upper ends of the tubes being maintained above the water level. lVhen the water level falls below a `predetermined minimum the cut-out switch 48 will be operated to (leenergize the inagnet 4A for unlocking the switch 37 and for effecting the opening of the circuit to the heating elements, a safe and dependable operation being thereby provided.

lfhile have shown my device in the preferred form will be obvious that many changes and modiications may be made in the structure disclosed without departing from the spirit of the invention7 defined in llowing claims.

In an electric boiler., a boiler casing, a fioat movable therein and :idapted to follow the changing liquid level in the boiler, heatlng elements carried by the fioat and means for guiding the fioat in its movement in the boiler, the said means comprising a stem slida-bly receiving the Said fioat.

:nan electric boiler, a boiler casing, a

1' hollow metallic fioat movable therein and adap'fd to follow the changing liquid level in the boiler, electrical heating elements' insulatably carried by the fioat and means for guiding the fioat in its movement in the boiler, the said means comprising a stem connected to the boiler' casing, the said stem slidably receiving the said fioat.

3. In an electric boiler and steam generator, al casing, a fioat movable therein and adapted to follow the changing liquid level in the boiler, tubu'lar electrical heating elements carried by the fioat' and movable therewith, the arrangement being such that the upper ends of the tubular elements are exposed above the water level and means for guiding the fioat in its movement in the boiler with the said tubeends maintained above the water level, the said means comprising a centrally located stationarily mounted stem receiving the said fioat for free slidable movement thereon.

4. lin an electric boiler, a vboiler casing including a boiler closure therefor, a-fioat movable within the casing and adapted to follow the changing liquid level in the boiler, heating elements carried by the fioat and means for guiding the fioat in its movenient in the boiler, the said means comprising a stem carried by the said closure and siidably receiving the said fioat and means i stem', the construction being-such that the float and the stem are removable as a unit with the boiler closure.

5. In an electric boiler, a boiler closure, a'

stem carried thereby, a float slidably movable on the stem and heating elements carried by the float.

6. In an electric boiler, a boiler closure, a stem carried thereby and located centrally thereof, a hollow metallic float slidably movable on the said Istem and a plurality of electrical heating tubes carried by`th'e float for movement therewith. v

7. In an electric boiler, a heating apparatus adapted for following the changing liquid level in the boiler, the'said heating apparatus comprising a hollowisubstantially ball shape'd float and a series of tubular electrical resistance elements mounted on the float and arranged vcircumferentially thereon.

float, a plurality of tubular electrical resistance elements carried bv the float and arranged peripherally thereof and means for supporting the vtubular elements on the float,

the said means comprising a resilient sheathl interposed between the float and the heating elements and a peripheral clamping band arranged externally to the-heating elements for clamping the same in position on the float.

9. In an electric boiler, a boiler casing, a float movable therein and adapted to follow the changing liquid level in the said boiler, heating elements carried by the float, an electricalcircuit therefor and provisions for controlling the said circuit to the heating velements including switch means controlled 'by the movement of the float.

10. In an electric boiler, a boiler casing, a' float movable therein and adapted'to follow the changing liquid level: in v'the' said boiler, heating elements carried, by the'float, an electrical circuit therefor and provisionsv for controlling the said circuit to the heating elements controlled by the movementof the float.

11. In an electric boiler, a boiler casing, a float movable therein and adapted to follow the changing liquid level in the boiler, tubular electrical' resistance heating elements carried by the float adapted for connection to an electrical circuit and provisions for controlling the said 'circuit to' thefjheating elements'controlledby the movement of the said float. J i

12. In an electric boiler, a boiler` closure,

a float carried 'by the boiler closure and adapted for movement within" the boiler for the changing liquid level therein,

following heating-'e ements carried by the float, an electrcalclr'cuittherefor and provisions'carried by the said closure for controlling the said circuit to the heating elements, the said provisions being controlled by movement of the said float.

13. In an electric boiler, a float movable in the boiler and adapted to follow the changing liquid level therein, electrical heating elements carried by the float, a circuit therefor, a cut-out switch movable for controlling the said circuit to theI heating elements, the Said switch being operated by movement of the float in the boiler.

. 14. In an electric boiler, a boiler casing, a floatmovable therein and adapted to follow the changing liquid level in the boiler, heating elements carried by the float, means for guiding the float in its movement in the boiler comprising a stem slidably receiving the said float, an electrical circuit for the heating elements, switch means for controlling the said circuitvand provisions for operating the said switch means, the said provisions being also movable on the stem and controlled by the movement of the said float.

15. In an electric boiler, a boiler closure, a float movable within the boiler and adapted to follow the changing liquid level therein, heating elements carried by the`float, means for guiding the float in its movement in the boiler comprising a stem carried by the said closure and slidably receiving the said float, an electrical circuit for the heatfor the heating elements, lswitch provisions.

for controlling the said circuit and means movable onthe stem forv Operating the said provisions, the said means being movable to two positions on the sal stem, the construction beingsuch that when'the floatis moved to a predetermined upper level the said means will be moved to one position and when the float -is moved to a predetermined lower level the said means will be moved to its other position.

17. In an electric boiler, a boiler casin a float movable therein and adapted to ollow the changing liquid level in the'boiler, electrical heating elements carried by the float, a circuit therefor, a control switch in said circuit and means for preventing operability of the. said controlswitch under abnormal boiler'conditiona? the said means including provisions ai'renged within the css,-

ing and Controlled by the position of the said float.

18. In an electric boiler, a boiler casing, a float movable therein and adapted to follow the changing liquid level in the boiler, electrical heating elements carried by the float, a Circuit therefor, a control switch in said Circuit and means 'for preventing operability of the said control switch under abnormal boiler conditions, the said means including a second switch arranged within the Casing and controlled by the position of the said float.

'19. In an electric boiler, a boiler casing, a. float movable therein and adapted to follow the changing liquid level in the boiler, an electrical Circuit, a switch in said circuit andmeans for preventing operation of the said switch under abnormal boilei` Conditions, the said means including provisions arranged within the casing and Controlled by the position of the said float.

20. In an electric boiler, a boiler casing, a fioat movable therein and adapted to follow the changing liquid level in the boiler, electrical heating elements carried by the float, a Circuit therefor, a control switch in said Circuit normally movable to open position,

a looking means therefor for holding the switch closed under normal boiler conditions and means for controlling the operation of the said looking means for preventing operability thereof under abnormal boiler conditions, the said means including provisions arranged within the casing and Controlled by tlie position of the said float.

21. In an electric boiler` a boiler casing, a float movable therein a'nd adapted to follow the changing liquid level in the boiler, electrical heating elements carried by the float, a Circuit therefor, a control switch in said Circuit normally movable to open position, a looking means therefor for holding the switch closed undernormal boiler Conditions and means for controlling the operation of the said looking means for preventing operability thereof under abnormal boiler conditions, the said means including a solenoid for actuating the looking means and a. cut-out switch arranged within the casing and movable Ito open and closed position b movement of the said float.

22. n an electric boiler, a boiler casing, a float movable therein and adapted to follow the changing liquid level in the boiler, heatingr elements carried by the float and means for `rectilinearly guiding the float in its movement responsive to the changing liquid level in the boiler.

23. In an electric boiler, a boiler closure, guiding means carried thereby, a fioat guidedly movable on said guiding means and heatingr elements carried by the float.

24. In an electric boiler, a. boiler closure, a guiding means carried thereby and located Centrally thereof` a hollow metallic float guidedly movable on said guiding means and a plurality of electrical heating tubes carried by the float for movement therewith.

25. In an electric boiler.v a boiler' casing, a plurality of electrical heating elements floatingly movable within the casing, an electric Circuit therefor and provisiolns for controlling the said Circuit to the heating elements controlled by the movement of the same.

26. In an electric boiler, a boiler casing, a float movable therein and adapted to follow the changing liquid level in the said boiler,

floatable heating elements associated with v the float, an electrical Circuit therefor and provisions for controlling the said Circuit to the heating elements controlled by the movement of the float. 27. In an electric boiler, a boiler casing, floatable heating elements therein and means fo]l guiding the said heating elements for following the changing liquid'level in the boiler.

28. In an' electric boiler, a boiler Cas'ng, floatable electrical heating elements ther in, an electric Circuit therefor and means controlled by movement of the said floating heating elements for Controlling the operability of the said ,circuit.

` Siwgned at New York city, in the County of l\ew York and State of New York, this 3rd day of March, A. D. 1922.

' HYMAN E. COHEN.

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