US2386949A

US2386949A - Liquid heater

Info

Publication number: US2386949A
Application number: US509582A
Authority: US
Inventors: Henry W Hayward
Original assignee: Individual
Current assignee: Individual
Priority date: 1943-11-09
Filing date: 1943-11-09
Publication date: 1945-10-16
Anticipated expiration: 1962-10-16

Description

'O-ct. 16, s1945. H. w. HAYWARD LIQUID HEATER Filed Nav.. 9, 1943 5 sheets-snet 1 V.. AE.,

ILNFVENTOR. j W/ Oct. 16, 1945.

'H. w. HAYWARD LIQUID HEATER Filed Nov. 9, 1943 Wwmmm I 3 Sheets-Sheet 2 @my l @Ww/Wy oct; 16, 1945.

H. W. HAYWARD LIQUID HEATER Filed Nov. 9, 1943 3 Sheets-Sheet 3 EV'AM INVENTOR.

@my BY Patented Oct. 16, 1945 UNITEDY STATES PATENT OFFICE LIQUID HEATER f Henry W. Hayward, Irondequoit, N. Y.

Application November 9, 1943, Serial No. 509,582 16 claims. (01.219-39) This invention relates to liquid heaters, such, for example, as water heaters for residential installations, one object of the invention being to provide an improved and more practical and economical heater of the character described, adapted tov be heated by either gas burner means or electrical resistance elements, as desired.

Another object is to provide such a heater capable of furnishing an ample supply of hot water, or other liquid, with quick recovery of temperature after service demands thereon, while at the same time requiring heat input at a more constant rate.

' A further object is to afford a heater of the character described capable ofy maintaining in storage at al1 times a substantial quantity of hot Water suiicient for normal immediate needs, produced by a succession of heating periods so as to spread out over a relatively long time the total required heat input, thus combining the advantages of an instantaneous type heater with those of a slow recovery heater but Without the known disadvantages of such prior heaters.

Still a further object is to provide such a, heater having, in combination with the above features, an advantageous arrangement for reducing radiation losses and so additionally increasing the operating efiiciency.

To these and other ends the invention resides in certain improvements and combinations of parts, all as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the speciiication.

In the drawings:

Fig. l is a central, vertical section of a heater of the electrical type embodying the present in- Vention;

Fig. 2 is a horizontal section on the line 2a-2a in Fig. l;

Fig. 3 is an enlarged, sectional view illustrating the Mercoid type switch employed in the present embodiment;

Fig. 4 is a diagram of the electrical circuit employed in a heater of the type shown in Fig. l;

Fig. 5 is a View similar to Fig. 1 oi a modiiied embodiment of the invention, comprising gas burner heating means; y

Fig. 6 is a horizontal section on the line 15a-Ea in Fig. 5;

Fig. '7 is a vertical, sectional View on the line 'lo-'la in Fig. 5;

Fig. 8 is an enlarged, vertical view of the gas burner means shown in Fig. 5, and

Fig. 9 is a diagram of the electrical circuit for controlling the heating means shown in Fig. 5.

Cil

The preferred Yembodiment of the invention, herein disclosed by Way of illustration, comprises a combination of liquid heating and storing chambers one of Which,'herein termed the "primary storage container is employed to heat and hold a Substantial body of hot Water ready for immediate use, While the other termed the secondary storage container encompasses the primary container and serves as a preheating chamber, as Well as a means of insulating the primary container against heat losses, the heat being preferably supplied directly to and also interchanged between the containers in such a way as to insure rapid recovery after service demands and operating at a substantially constant rate of heat input.

Referring more particularly to the drawings, the primary rstorage container is shown at 20 (Figi) in the fonm of a vertically arranged, cylindrical, metal drum having at its top an outlet pipe 2l for supplying the heated water for use.A The secondary storage container is shown at 23 inthe form of an annular casing, the outer cylindrical walls of which are of substantially greater diameter than container v20, while the inner walls of container 23 are formed by the Walls of container 20 with which container 23 is connected in a fluid-tight manner by means of top flange 24 and the bottom 25 of container 23. The secondary container thus encloses an annular space, 26, of substantial capacity but is of substantially less height than container 2l), the upper' portion 21 of which extends above the top of container 23, preferably as an extension of its cylindrical lower portion, although such upper portion 21 may have any other suitable shape. Container 23 has communicating therewith a water inlet pipe 28, as shown.

As indicated above, the water, or other liquid to be heated, is introduced to the unit through 'pipe 28 connected with the secondary or outer container 23, and is discharged from the top of the primary or inner container 21 through the pipe 2l, and means are provided for the now of the Water from container 23 to container 20 to replace that withdrawn by service demands. Such means comprises, preferably, a suitable number of openings 29 in the lower portion of the common Wall 3H between the containers, these openings being shrouded by conducting baiiies or hoods 3|, open at their tops 32 which are positioned for communication with the upper portion of the secondary container 23. By this means the preheated water collecting in the upper portion of secondary container 23 may flow downwardly through the hoods 3| and openings 29 into the lower portion of the primary container 20, the openings 29 being located at approximately the level at which the Water temperature corresponds with that of the preheated water supplied from container 23,

Means are provided for directly heating the water in the lower portion of the primary container, 2B, from which the heat is transmitted through the common wall 3U to'preheat the water in the secondary container 23. While such a heating arrangement may be sufficient for some installations, it is preferred to provide means also for supplying heat directly to the water in the secondary container 23, and such a heating system, of the electrical resistance type, will now be` described.

The electrical heating means preferably comprises an electrical resistance heating element in the form of a horizontal loop 33 (Figs. 1, 2 and 4), supported by an outlet box 34 positioned in a recess 35 in the secondary container and having a liquid-tight t in an opening in primary container 20, with the heating element projecting into the primary container, as shown in Fig.' 2. A similar heating element is provided for the secondary container in the form of a vertically arranged and curved loop 35, carried by an outlet box 31 having a liquid-tight fit in an opening in the outer wall ofthe container, as shown,

heating elements

33 and 36 being both connected with temperature responsive elements located in the containers. l

Such temperature responsive elements preferably comprise a switch 38 of the Mercoid" type, f

illustrated in Fig. 3, which is connected to and oscillated by temperature responsive means of any known or suitable variety, as well understood in the art,'such devices being enclosed' in liquidtight housings projecting in liquid-tight arrangement through-openings inthe container walls. Each switch comprises a pair of

electrical terminals

39 and 40, extending in pairs in sealed rela-V tion through the ends 'ofthe glass tube 4l,'in which is a body of mercury 42 for electrically connecting the terminals of each pair as the tube 4| istipped to drive the mercury to one end or the other. One such temperature responsive de-` vice is located at 43 in the upper portion 21 of the primary container in which the hot water is stored for use. Another 'such device 44 is located in container 21 a short distance above device 43, while a third temperature responsive vdevice 4-5 is located in the upper portion of secondary container 23.

These temperature responsive devices are connected in circuit with the

heating elements

33 and 36, as shown in Fig. 4,`fron'1 which it will be seen' thattemperature responsive device 43 operates to connect one side 46 of-'thepower'line alternately with one or the other of the heating elements, being shown in position in Fig. 4 for energizingthe heating element 33 ofthe primary container. The circuit including the heating element 35 of the second-ary container includes the ai.

close the circuit including the heating means in the secondary container. When the temperature of the water reaches a predetermined high limit in the top of the secondary container, its temperature responsive element 45 and associated switch will then deenergize its heating element When a demand on the unit reduces the temperature at the temperature responsive element 43, so as to result in closing of its associated switch and the energizing of its heating element 33, then the circuit through the heating means of the secondary container will be open,

1 the separate heating means for the respective temperature responsive device 45 located in the tion of the primary container is heated down to Ythe level of the temperature responsive element 43, the associated switch will be operated to disconnect the'primary heating 6161116111133 @nd containers being thus operated in an alternating fashion which, with the continuous transfer of heat through the common wall between the containers, tends to produce a more uniform rate of heat input.

When the temperature at the responsive device 44 in the upper portion of the primary container reaches a predetermined high limit, it operates the associated switch to deenergize the heating means in bothcontainers until the temperature drops again within the desired operating range. It will be seen that the secondary container is not only heated in part from the primary container through their common wall surfaces, but serves, in addition, to insulate the lower portion of the primary container, and conserve the heat which would otherwise be radiated from it and otherwise dissipated and lost, Such encompassing location of the secondary container, on the outside of the primary container, presents water of lower temperature at the outer surfaces ofsuch portions of the unit to further reduce the dissipation of heat, and these features aiord a greatly increased operating eiciency. The compact association and design of the two containers, furthermore, is such as to facilitate the encasement thereof in a substantial jacket of efficient insulating material of any known or suitable variety indicated at48, as well understood in the art.

Starting with the inner or heating chamber full of water at, say 160 the thermostat 43 will deenergize thel heat' source. Heat transfer will immediately occur through the common wall between the containers into the water in the secondary or outer containerY so as to preheat it. This in time will cool the water in the primary cr inner container to a degree below the setting of its thermostat, thus reenergizing its heat source until its water is again raised to the setting of its thermostat and its heat again shut ofi. The hottest water will collect, of course, in the upper portion of the primary container, from which it is withdrawn, as required, through pipe 2l. On such withdrawal, makeup water which has been preheated and collected inthe top of the secondary container, will be admitted to the primary container through the hoods 3l and openings 29. .This will result in lowering the temperature of the water in the primary container and the reenergizing of its heating means, followed by reenergizing of the heating means in the secondary container, to supplement theV heat 'supplied by tansmission through the common wall. It will be noted, however, thatthe water'admitted to the primary container willlbe preheated to a temperature of, say, 100 F., as controlled by the setting of thermostat 45Y in the secondary container, so as to require further heating in the primary container through a range of only 60 F., thereby decreasing the heat input required in the primary demand on its storage supply.

Thus the heating operation and maintenance of temperature in the primary container will proceed in a series of steps of alternate operation of its heat source and loss of temperature to the secondary container, with the result that the temperature of the Water in the primary contaner will be maintained nearly constant, while intermittently transferring heat to the encompassing secondary container for additional storage in the form of preheated water. The secondary container may or may not be directly supplied with heat depending, for example, upon the application to it of the separate heating means described, or, when applied, upon the setting of its temperature responsive element. Such direct heating of the secondary container may be preferable, for example, in installations operated at a relatively high rate of duty.

ln Figs. 5 to 9, inclusive, there is shown a modified construction comprising gas burner heating means for one or both containers. This embodiment employs a similar primary container 49, with an outlet connection 5D, and an encompassing secondary container 5l, which has the same construction and arrangement as described above, except for a somewhat larger diameter. Similar openings 52 are provided in the common wall between the containers, shrouded by conducting hoods 53, communicating with the upper portion of the secondary container, which is provided with an inlet connection 54.

In this modified embodiment, however, the electrical resistance heating elements are replaced by

fuel gas burners

55 and 56, each of a size suitable for its associated container. The products of combustion from burner 55 pass into a iiue 57, which rises through the water in the primary container 49, to heat the same and out through a stack 5S. The products of combustion from burner 56 pass into a nue 59, which rises through the water in the secondary container and to the stack 58.

The fuel gas is supplied to burner 55 from a main connection 6B controlled by a valve 5l operated by a horizontal solenoid 62 and spring 53, as well understood in the art. A branch pipe 64, leading directly to burner 55, is similarly controlled by a. valve 65 operated by a vertically arranged solenoid G6, as well understood in the art.

Burner 55 is supplied through a branch line 51, 'y'

similarly controlled by a valve 68, operated by a similar solenoid E9. At 'm is a pilot means for lighting each burner supplied through a pipe 1|.

The temperature responsive elements 12, 'i3 and 14, associated respectively with Mercoid switches 75, 15 and l?, are of the same construction and arrangement as explained in connection with the embodiment first described, and are employed to control the

solenoids

65, 5S and 52. Element T2, with its switch 15, contro-ls solenoid 66 and the circuit of solenoid 69, for alternate operatic-n of the

valves

65 and 68, Element 14. with its switch 11, directly controls solenoid 59 and valve 68, while element '13, with its switch T6, controls solenoid 62 and main valve 5I. operation of this control system is the same as that of the electrical system of the embodiment nrst described, with corresponding operatic-n of the containers and the unit as a whole.

It will be apparent from the description of the foregoing embodiments of the invention that they provide a unit having a heat storage chamber elevated above and protected from the cooling effect of the secondary chamber, so as to afford an ample reservoir of heated water held ready The "l for instant use. The concentric and encompassing preheating container, with its common wall surfaces, absorbs a large proportion of the heat dissipated from the primary container to provide preheating of the water supply, assisted by direct heating means, if desired, thus contributing to a rapid recovery rate and efiicient operation. A further advantage resides in a more constant rate of heat and power input, which facilitates eicient service on the part of the electrical or gas power utility by which the unit is supplied.

It will thus be seen that the invention accomplishes its objects and while it has been described in preferred forni and in detail, it is to be understood that such description is intended in an illustrative. rather than a limiting sense, as it is contemplated that various changes in the construction and arrangement of the parts will readily occur to those skilled in the art Within the spirit of the invention and the scope of the ap pended claims.

I claim:

1. A liquid heater comprising a. primary storage container having communicating upper and lower portions, said upper portion being adapted and arranged to store a supply of heated liquid ready for use and having a liquid outlet, a secondary storage container having a liquid inlet, means for heating the liquid in said primary container, said lower portion only of said primary container and said secondary container having common wall surfaces therebetween of substantial extent for transferring heat from the liquid in said lower portion only of said primary container to the liquid in said secondary container to preheat the same, and a connection from the upper portion of said secondary container to said lower portion of said primary container for transmitting thereto the liquid preheated in said secondary container.

2. A liquid heater comprising a primary storage container having a thermally insulated upper portion provided with a liquid outlet, a secondary storage container having a liquid inlet, means for heating the liquid in said primary container, said containers having wall surfaces common to substantially the full height of said secondary container but to the lower portion only of said primary container, for transferring heat from the liquid in the lower portion only of said primary container to the liquid in said secondary containe;` to preheat the same, without substantially affecting the temperature of the supply of heated liquid contained in the upper portion of said primary container, and a connection from the said secondary container to said lower portion of said primary container for transmitting thereto the liquid preheated in said secondary container.

3. A liquidv heater comprising a primary storage container having a liquid outlet, a secondary storage container having a liquid inlet, means for heating the liquid in said primary container, said primary container having an upper po-rtion extending above said secondary container for storing heated liquid ready for use and said containers having common wall surfaces arranged therebetween for transferring heat from the liquid iny the lower portion only of said primary container to the liquid in said secondary container to preheat the same, without substantially affecting the temperature of said heated liquid in said upper portion, and a connection from said secondary container to said lower portion of said primary container for transmitting thereto the liquid preheated in said secondary container.

4.'.A liquid heater comprising a primary storage container having a liquid outlet, a secondary storage container having a liquid inlet, means for Vheating the liquid in said primary container, said primary container having an upper portion extending above said secondary container and provided with said outlet for storing and supplying heated liquid ready for use and said containers yhaving common wall surfaces positioned therebetween below said upper portion of said primary container for transferring heat from' the liquid in the lower portion of said primary container to the liquid in said secondary container to preheat the same, and a connection leading downwardly from the liquid in the upper portion of said secondary container to a region of liquid having substantially the same temperature in the lower portion of said primary container for transmitting thereto the liquid preheated in said secondary container.

5. A liquid heater comprising a primary 'storage container having communicating upper and lower portions, said upper portion being-v provided' with a liquid outlet, a secondary storage container of substantially annular shape encircling said lower portion only of said primary container and having a liquid inlet, means for heating the liquid in said primary container, said Vlower portion only of said primary container and said secondary container having common wall surfaces therebetween of substantial extent for transferring heat from the liquid in said lower portion of said primary container to the liquid in said secondary container to preheat the same, without substantially affecting the temperature of said heated liquid -in said upper portion, and a connection from the upper portion of said secondary container to said lower portion of said primary container for transmitting thereto the Y liquid preheated in said secondary container.

6.- A liquid heater comprising a primaryfstor- 'age container having a liquid outlet,` a secondary storage container of substantially annular shape encircling the lower portion only of said primary container and having a liquid inlet means immersed in and surrounded by the liquid of said primary container for heating the same,r the wall of said primary container and the inner wall of said secondary container comprising common metal wall surfaces therebetween for transmitting heat from the liquid in said lower portion only of said primary container to the liquid in said secondary container to preheat the same, without substantially affecting the temperature of the supply of heated liquid contained in the upper portion of said primary container, and a connection from the upper portion of said secondary container to said lower portion of said primary container intermediate the top and bottom thereof for transmitting thereto the liquid preheated in said secondary container.

'7.' A liquid heater comprising a primary storage container having communicating upper and lower portions, said upper portion having a liquid outlet, a secondary storage container having a liquid inlet, separate means for heating said containers, respectively, temperature responsive means in said containers for controlling each of said heating means, said lower portion of said primary container and said secondary container having common metal wall surfaces therebetween of substantial extent for transferring heat from the liquid in said lower portion of said pri- Cil -mary container toxthe liquid in said secondary container to' additionally preheat the same, without substantially aiecting the temperature of the supply of heated liquid contained in the upper portion of said primary container, and a connection from said upper portion of said secondary containerto said lower portion of saidprimary container for transmitting thereto the liquid preheated in said secondary container.

8. A liquid heater comprising a primary-storage container having a liquid outlet, a secondary storage container of substantially annular shape encircling the lower portion only of said primary container and having al liquid inlet, separate means for heating said containers, respectively, temperature responsive means in said containers for controlling each of said heating means,v the wall of said lower portion of said 4primary container and the inner wall of said secondary container providing common wall surfaces therebetween for transferring heat from the liquid in said lower portion of said primary container to the liquid in said secondary. container to additionally preheat the same, without substantially aifecting the temperature of the supply of heated liquid contained inthe upper portion ofv said primary container, and a connection from the upper portionv of said secondary container to said lower portion of said primary container for transmitting thereto the liquid preheated in said secondary container.

9. A liquid heater comprising a primary storage container having communicating upper vand lower portions, said upper portion-being adapted and arranged tostore a supply of heated liquid ready for use and provided with a liquid outlet, a secondary storage container having a liquid inlet, means including a separate gas burner for each of said containers having a iiue extending through the liquid therein for heating the same,

,means in said containers for controlling said gas burners, said lower portion only of said primary container and said secondary container having common wall surfaces therebetween for transferring heat from the liquid in said lower portion only of said primary container to the liquid in said secondary container to additionally preheat the same, and a connection from the upper portionrof said secondary container to said lower portion of said primary container` for transmitting thereto the liquid preheated in said secondary container.

10. A liquid heater-comprisingra primary storage container-having a liquid outlet, a secondary storage container having a liquid inlet, means including a separate gas burner for each of said containers having a flue extending throughV the liquid therein for heating the same, means in said containers for controlling said gas burners, said primary container having an upper portion extending above said secondary container for storing heated liquid ready for use and the lower portion of said primary container and saidv secondary container having common wall surfaces therebetween for transferring heat from the liquid in the lower portion of said primary container to the liquid` in said secondary container to additionally preheat the same, and a connection from the upper portion-of said secondary container to said lower portion of said primary container for transmitting thereto the liquid preheated in said secondary container. Y t t l1. A liquid heater comprising a primary storage container having communicating upper and lower portions, said upper portion being adapted and arranged to store a supply of heated liquid ready for use and having a, liquid outlet, a secondary storage container having a liquid inlet, means including a separate gas burner for each of said containers having a flue extending through the liquid therein for heating the same, temperature responsive means in said primary container arranged to effect the energizing of said heating means in alternation with each other, said lower portion of said primary container and said secondary container having common wall surfaces therebetween for transferring heat from the liquid in sai-d lower portion of said primary container to the liquid in said secondary container to additionally preheat the same, and a connection from the upper portion of said secondary container to said lower portion of said primary container for transmitting thereto the liquid preheated in said secondary container.

l2. A liquid heater comprising a primary storage container having a liquid outlet, a secondary storage container having a liquid inlet, means including an electrical heating element immersed in and surrounded by the liquid in each of said containers, for heating the same, temperature responsive means in said containers for controlling said elements, said primary container having an upper portion extending above said secon-dary container for storing heated liquid ready for use and the lower portion of said primary container and said secondary container having common wall surfaces therebetween for transferring heat from the liquid in the lower portion of said primary container to the liquid in said secondary container to additionally preheat the same, and a connection from said secondary container to said lower portion olf said primary container for transmitting thereto the liquid preheated in said secondary container.

13. A liquid heater comprising a primary storage container having` a liquid outlet, a secondary storage container having a liquid inlet, separate means for heating the liquid in said containers, respectively, temperature responsive means in said primary container arranged to eiect the energizing of said heating means in alternation with each other, said containers having common wall surfaces therebetween of substantial extent for transferring heat from the liquid in said primary container to the liquid in said secondary container to additionally preheat the same, and a connection from said secondary container to said primary container for transmitting thereto the liquid preheated in said secondary container.

14. A liquid heater comprising a primary storr age container having communicating upper and lower portions, said upper portion being adapted and arranged to store a supply of heated liquid and having a liquid outlet, a secondary storage container having a liquid inlet, separate means for heating the liquid in said containers, respectively, temperature responsive means in said primary container arranged to elect the energizing of said heating means in alternation with each other, said lower portion only of said primary container and said secondary container having common wall surfaces therebetween for transferring heat from the liquid in said lower portion only of said primary container to the liquid in said secondary container to additionally preheat the same, and a connection from said secondary container to said lower portion of said primary container for transmitting thereto the liquid preheated in said secondary container.

15. A liquid heater comprising a primary storage container having a liquid outlet, a secondary storage container having a liquid inlet, separate means for heating the liquid in said containers, respectively, temperature responsive means in said primary container arranged to effect the energizing of said heating means in alternation with each other, temperature responsive means in each of said containers for deenergizing the heating means thereof at a predetermined maximum temperature, respectively, said containers having common wall surfaces therebetween of substantial extent for transferring heat from the liquid in said primary container to the liquid in said secondary container to additionally preheat the same, and a connection from said secondary container to said primary container for transmitting thereto the liquid preheated in said secondary container.

16. A liquid heater comprising a primary storage container having communicating upper and lower portions, said upper portion being adapted and arranged to store a supply of heated liquid and having a liquid outlet, a secondary storage container having a liquid inlet, separate means for heating the liquid in said containers, respectively, temperature responsive means in said primary container arranged to effect the energizing of said heating means in alternation with each other, temperature responsive means in each of said containers for deenergizing the heating means thereof at a predetermined maximum temperature, respectively, said lower portion only of said primary container and said secondary container having common wall surfaces therebetween for transferring heat from the liquid in said lower portion only of said primary container to the liquid in said secondary container to additionally preheat the same, without substantially affecting the temperature of said heated liquid in said upper portion of said primary container, and a connection from the upper portion of said secondary container to said lower portion of said primary container for transmitting thereto the liquid preheated in said secondary container.

HENRY W. I-LAYWARD.