US2416514A - Liquid fuel feeding means - Google Patents

Description

1947. L. s. CHADWICK LIQUID FUEL FEEDING MEANS Filed March 13., 1943 3 Sheets-Sheet 1 R3 INVENTOR.

/55 .53 (knew/ck Feb. 25, 1947. s CHADWICK 2,416,514

LIQU-ID FUEL FEEDING MEANS Filed March 13, 1943 3 Sheets-Sheet 2 I III! mmvron Lee-52 Cqnaw/cK BY flTTOlP/VEYS Feb. 25, 1947.

L. CHADWICK LIQUID FUEL FEEDING MEANS Filed March 13, 1943 3 Sheets-Sheet 3 INVEN TOR.

LEE .5! 611,40 W/CK BY 4w HAM Patented Feb. 25, 1947 I LIQUID FUELFEEDING MEANS Lee S. ChadwickfShaker Heights, Ohio, assignor to Perfection Stove Company, Cleveland, Ohio, a corporation of Ohio Application March 13, 1943, Serial No. 479,042

1 t This invention relates, generally, to liquid fuel burning apparatus that is especially suitable for use in furnaces of heating systems of houses or other buildings, and whose operating range includes low and relatively'higher fires, 'and in which, through suitable feeding and governing mechanism, the burner is constantly supplied with fuel-at no time, so long as the apparatus is moderation, with less than enough to sustain operation atlow fire, and at certain times with sufficient additional fuel to produce higher fire. More particularly, the invention has, to do with improved means for use in such apparatus for feeding fuel at the rate required for low fire.

When apparatus of the class referred to is op- 6 Claims. (01. 137-48) wick clear of the liquid supply obviously arrests the flow.

A further object of the invention is to provide a simple andconvenient means of adjusting the wick; and a still further object is to provide a construction that 'is designed to facilitate and cheapen the manufacture and fabrication of its parts, the majority of which are die-stamped and formed from sheet metal, and are adapted for crating at low fire, which amounts practically to pilot fire, very little fuel is required. For example: In a size furnace burner wherewith the invention is intended for use, little more than one-half gallon of fuel is fed every 24 hours for the purpose of sustaining operation at low fire,

, in sufficient amount to supply the, other sump for and this amounts to approximately one drop I every two seconds. fore, that uniform and dependable feeding of the fuel at so low'a rate' presents a problem, and contrivances heretofore employed for the purpose have generally proven to be unsatisfactory and unreliable, especially those wherein the control of the flow of fuel. is accomplished by means of orifices, as is the case with practically'all types of valves. I

It is the fundamental object of the present invention to provide a relatively simple and thoroughly reliable 'fuel feeding means involving a capillary siphon for feeding the liquid fuel to the burner in limited quantity, such as that required for lowiire; and a further object is topro- It will be apparent, thereconnection to one another by welding.

.11 further object is to provide, in apparatus of the aforesaid class, aliquid fuel burner involving two sumps to one of which the fuel is fed by said capillary siphon and wherein it is concentrated for low-fire, while valve controlled means is employed for delivering additional fuel to the burner the purpose of producing high fire.

The foregoing objects, with others hereinafter appearing, are attained in the embodlment'of the invention illustrated inthe accompanying drawings wherein Fig. 1 is a diagrammatic representation of a liquid fuel burning apparatus incorporating the invention; Fig. 2 is an elevational view of the fuel feeding means involving the capillary or wick siphon; Fig. 3 is a plan view thereof with a part of the cover broken away; Fig. 4 is a central vertical section through the fuel feeding means on the line 4-4 of Fig. 2; Fig. 5 is ahorizontal section on the lines I5 of Figs.4 and 6: Fig. 615 a vertical section on the line,6l of Fig.

4; Fig. '7 is a perspective view of the wick carrier,

. with parts broken away in order to better show wide means whereby said capillary siphon may be adjusted to vary and control the amount of fuel feed, or to stop the feed entirely.

The capillary siphon consists of an inverted U-shaped wick, and in the present preferred conits construction, and Fi 8 is a perspective view of the adjusting screw supporting bracket.

In the liquid fuel burning apparatus schematically illustrated in Fig. 1, a burner of the so-called pot or bowl type is employed, the burner bowl being designated generally by the reference numeral Land the same is suitably supported with struction, the wick is supported by a carrier astride a partition or barrier located in, the com- .municative connections between a constant level its top wall 2 in spaced relation to the bottom wall 3 of the combustion chamber 4. Said walls 2 and I have alignedopenings. that of wall 2 being surrounded by'a downwardly and inwardly turned flange}, while the opening of the wall I is surrounded by a depending flange '8. The

' flanges i and B are spaced apart to provide a slot supply to the burner solelyby gravity. Thewick is unsheathed intermediate its ends (in contradistinction to siphon tubes containing wicks) so that its siphonic action is confined entirely to that dependent upon oapillarlty; and changes in the rate of flow through the wick are effected by raising and lowering the wick. Elevating the x i0 in the peripheral wall of the bowl.

8 for the admission of secondary air tothe burner bowl, as will hereinafter more fully appear. Primaryair is admitted through perforations 9 and A latively large lighting and cleanout opening is made in said wall and the same is surroundedby a, neck [2 that is normally closed by a plug I I.

1 3 shown ashavinz' a bayonet joint connection with the neck.

Liquid fuel issupplied to the above described combustion apparatus from a suitable source, such astliat represented by a tank i5, through a fuel feeding and governing system which I shall now describe. A pipe I 6, shown as including a,

valve 5 leads from the tank l5 to a receptacle II. The pipe communicates with said receptacle through a port [5- controlled by a valve 20. A spring 2| tends to lift the valve from its seat, and the valve is closed by a' float 22 that is carried by a lever 23; fulcrumed on a pivot pin 24 suitably supported in the receptacle IT, as by having its" ends connected to the side walls of the receptacle. The end of .the lever 25 remote from the float bears against the head of the valve 20. This float mechanism, as will be readily understood, serves said sump being constituted of a relatively small cup-likeelement the perimeter of which is spaced 30 from the receiving part 51 to the delivery part 58 above the bottom of a second and larger surrounding sump 29, formed by the depressed'cem;

tra] portion of said bottom wall. The tubular extension 21 is closed at its outer end, desirably by a screw cap 30 which may be removed for the purpose of cleaning the extension and sump 28.

Operating with a sliding fit within the overflow tube 251s a valve member 32 which is formed with a slot 32 at its lower end. The valve memberextends freely through an opening in the cover .4 transformer maybe in the house circuit represented by the'conductors 50 and II, in the latter of which is shown a manually operated switch 52.

The fuel feeding means involving the capillary or wick siphon hereinbefore referred to, for supplying fuel in very limited amount to the burner, consists of a casing designated generally by the reference numeral 55 and which is divided by a barrier or partition 55 into a receiving part 51 and a delivery part 58. Said barrier or partition extends from one side wall to the other of the casing 55, as will hereinafter more fully appear, and it rises from the bottom of the casing to a substantial distance above the level of liquid in the receptacle I1. The receiving part 51 is supplied with liquid fuel from the receptacle ll through a pipe 59, all of which is below the liquid 1 level maintained in said receptacle. Consequently fuel is constantly present in the receiving part 51 to the same-level as that prevailing in said receptacle. The delivery part 58 communicates with the burner through a pipe 50, through part of the previously mentioned pipe 26, and the tu- "bular extension 21. An inverted U-shaped wick 52 is sustained by a carrier 63 (later to be described in detail) astride the partition 56. Through capillary and siphonic action of this wick, the liquid fuel is transported at a slow rate from which it flows through'the previously described connections to the sump 28. While the burner is operating atlow on pilot fire, the fuel is consumed at such a rate that the level of the fuel is well below the top of the sump 28, as illustrated in Fig. 1 of the drawings; and obviously this level is further dependent upon the rate of fuel supply, and such supply, in turn,.is'go-vemed by the vertical adjustment of the Wick 24 of'the receptacle I1, and said member may be '40 which is accomplished by means of a screw 65 lifted to uncover a Part of the slot 23 thereby to permit liquid fuel to flow from ,the receptacle through the overflow tube 25, pipe 25 and extension 21 to the sump 25 from which it overflows into the sump 29. In the absence of combustion,

and with the valve 6' open and the valve member 52 lifted to uncover the slot 32, fuel willaccumulate within the sumps 28 and 29 to the depth incase the flre is extinguished from any cause, the

combustion apparatus will not overflow, it being understood that, when both branches of the wick siphon 62 are equally submerged, the wick will cease to function as a siphon.

According to the present illustration, the valve member 32 is automatically operated by a thermostatic element in the form of a bimetallic strip 35 that is rigidly connected at one end to a bracket 36, shown as mounted on the cover 24 of the receptacle 11. At its end opposite said bracket, the strip 35 has connection through a member 31 and a link 38 with the upper end of the valve member 32. Attached to one side of the bimetal strip 35 is an electrical resistance heater 40 to which is supplied current from the secondary winding 4| of a transformer 42 through a conductor 43. The other terminal of the heater is connected through a conductor 44 with a, contact element 45 of a so-called room thermostat 45. From the other or movable contact element 4'! of said thermostat leads conductor 48 'to the opposite end of the secondary winding 4| of the transformer. The primary winding .9 Of the that is rotatably supported within the casing 55 in a manner hereinafter to be described, said screw having threaded engagement with'a part 86 of the wick carrier 52.

I shall now describe in detail the structural 50 formed of sheet metal. These casing members are applied to the oppositesides of a structural gral parts the previously mentioned barrier or partition and a supporting bracket 13 that may be attached to a convenient part of the apparatus for supporting the casing 55 insproper" relation to the burner l and receptacle IT. The pipes 59 and 50, that communicate respectively with the receiving part 51 and the delivery part 58 of the casing 55, have their upper ends proiected through apertures in the bottoms of the casing members and suitably attached thereto with a leakproof joint, as by welding. Above the plane of the upper edge of the partition 56, the

edges of the corresponding side walls of the two casing members It and H are welded together in abutting relation, while below said plane, said edges, and those across the bottom, are flanged outwardly and bear against the opposite sides of the :element 12 to which they. are welded.

The wick carrier hereinbefore referred to and designated generally by the reference numeral 53, consists of two identical plates 15 (Fig. 7) that are connected at their upper ends, as by welding,

to the opposite sides of a spacer 16. This spacer is turned laterally above said plates to provide the previously mentioned part 68 that is formed with a threaded hole 11. The plates have transverse slots 18 that are located near their upper ends and register with a notch 19 of the same area in the spacer 18. At their lower ends the plates 15 are provided with lugs 80 that are turned outwardly and thence upwardly in spaced I relation to the body portions of the'plates.' {"'Engaged through the slots 18 and the notch 19 is a wick 82 of suitable material, such, as asbestos webbing. The wick is drawn down along the outer sides of the plates 15 and has its ends clamped between the plates and-the clinched. in lugs 80. Thus, the wick 82 is given an inverted U-shape, and is disposed astride the barrier or partition 56 when the carrier is lowered-thereover.

To adjust the wick vertically with respect to. the liquid fuel level for the purpose, of changing the rate at which the fuel is fed, orifdr stopping the feed altogether, I employ the previously mentioned screw 65 which is projected downwardly through a threadless aperture 85 formed in a lateral extension 86 of a bracket 81. (Fig. 8) that the heater 40. Under the influence of the-higher tact. element lland maintain open the circuit that includes the secondary ll of the transformer andthe resistance heater 40 that is supported in heatexchanging relation to and preferably by the bimetal strip 35. A drop in temperature be low said range will cause the contact element 41 to swinginto engagement with the contact element "and close said circuit thereby toenergize uncover the slot 33- and allow liquid fuel to pass from the receptacle II through the previously described connections to the burner. This fuel,

' augmenting the quantity fed by the capillary or enlarging the fire within the burner bowl 'I wick siphon 62, will flood the sump 28 and cause it to overflow into thesump 29 thereby greatly der these conditions the enlarged volume of vapors generated within the lower portion of the is fastened to a side wall of the casing 58 by end is piloted-in a bearing aperture of a lug 90 that is attached to and extends inwardly from the casing wall. A flanged cover 92 is telescoped over the upper end of the casing 55 and is apertured for the passage of the screws BI. The cover .82 has a hole 93 through which the upper end of the screw 65 extends so that the screw may be conveniently turned by means of its knurled head for the purpose of adjusting the wick or raising it clear of the liquid fuel supply. To prevent accidental dislodgement of the lower end of the screw from the lug 90, an abutment 84, such as a cotter pin, may be applied to the screw below the extension 88. i

In considering the operationof the apparatus it will be assumed that the valve 8' is open and oil is present in the system and that the burner has been ignited, asby removing the plug i3,'pro- Jecting a lighted match or taper through the opening of the neck l2, and replacing the plug.

and, incidentally, air entering through the slot 8, rise into the combustion chamber I and are carried away through the usual flue connections (not shown). The capillary or wick siphon 82 is adjusted with respect to the liquid level in the receiving part .51 of the casing 55 (which, obviously, is the same as that maintained in the receptacle l1) so as to feed fuel at a rate that will produce a flame of the desired volume for low fire, a shallow pool of fuel being maintained in the sump 28 under these conditions.

The room thermostat", as the term implies. is situated in a room or other space that is to be heated by the apparatus, and when the temperature of said room or space is within the range for which the thermostat is set-for example, between 70 and 72 F.-the movable contact element 41 will be in spaced relation to the conbowl will be supplied with primary air through the openings Q and I0 and, upon reaching the plane of the slot 8, will be rendered highly combustiblev by the addition of secondary air entering through said slot and will vigorously burn in the combustion chamber 4.

The high flre condition will continue until sufficient heat has been delivered to the room or space to which the thermostat 46 is exposed to cause the contact element 41 to swing away from the contact element 45 and open the circuit of the heater 40. As the heater cools the bimetal strip 35 will return to its former position and lower the valve member 32 sufficiently to close the slot 33 thereby to shut off the supplyof fuel ,to the burner other than that continually fed by the capillary or wick siphon 82.

This invention i not to be confused with liquid fuel feeds involving siphon tubes that are fllled with absorbent material which may be in the form of a continuous wick and serves to initiate flow through the tube. While in those cases the absorbent material or wick may strictly speaking, function as a, capillar siphon, the siphonic action thereof is so inferior tothat of the tubular siphon that vertical adlustment of the unit has no appreciable effect in changing the rate of flow through a the unit. I

Having thus described my invention, what I claim is:

- 1. Liquid fuel feeding means comprising a cas-' ing, a partition disposed transversely of the casing and extending from the bottom thereof to a given height within the casing, inlet and outlet connec-- tions communicating with the casing adjacent the bottom thereof on opposite sides of said partition, a rigid wick carrier including branches depending on opposite sides of the partition, a wick supported in inverted U-shaped formation by said carrier with its end portions extended downwardly along the branches of the carrier and secured thereto, the carrier including a lateral extension adjacent its upper end, said extension being provided with a threaded hole, a bracket projecting from the wall of the casing in vertically spaced relation to said extension and having an aperture height within the casing, inlet and outlet cone nections communicating with the casing adjacent the bottom thereof on opposite sides of said partition, a rigid wick carrier including branches depending on opposite sides of the partition, the branches having lugs at their lower ends, a wick supported in inverted U-shaped formation by said carrier with the end portions thereof extended 1 downwardly along the branches of the carrier and secured thereto by the aforesaid lugs, the carrier including a lateral extension adjacent its 'upper' end provided with a threaded hole, a

bracket projecting from the wall of the casing in vertically spaced relation to said extension and having an aperture in alignment with the hole;

in said extension, a screw engaged downwardly through said aperture with its head bearing upon said bracket and threadedly engaged through said.

'partment and for maintaining a substantially constant liquid leveltherein, an inverted U- hole, means on the casing wherein the lower end of the screw has bearing. and

a cover for said casing.

ing, a partition extending screw the lower portion of said casing, inlet and outlet connections com-, municating with the casing adjacent the bottom thereof on opposite sides of said partition, respectively, an adjusting screw, means supporting the screw for rotation on a verticalaxis adjacent the top of the casing, a wick carrier including a spacer 3. Liquid fuel feeding means comprising a cas disposed above the partition and in the plane thereof, the spacer being provided with a lateral 'extension having' threaded engagement with the screw, two plates incorporated in the wick carrier, one arranged on each side In said partition and having its upper end secured to said spacer, said plates having slots adjacent their upper ends, and a wick projected through said slots and havingits'end portions carried down alongside and secured to the plates.

4. Liquid fuel feeding means ,comprising a casing composed of two substantially identical members, a supporting element including a part,

comprising a partition on opposite sides of. which the lower portions of said members are disposed,

upper edge of said partition being welded toand to which said edge portions are welded, the edges of said members above the plane of the gether, inlet and outlet connections communicating with the'casing adjacent the bottom thereof on opposite sides'of said partition, a bracket '50 top thereof, the same having a laterally exsecured to a wall of, the casing adjacent the tended lug provided with an aperture, a second lug extending-from said wall and having a bearing aperture in axia1 alignmentwith the former aperture, a wick carrier having a lateral extension disposed between the aforesaid lugs and ture, an inverted U-shaped wick sustained by shaped wick, a rigid carrier supporting the same astride said partition, and means for adjusting the carrier bodily vertically of said partition to and between a position wherein the lower end-oi the branches of the wick are a material distance below said liquid level, and a position wherein the branch of the wick that is in the receiving part of the casing is above said level.

6. In a liquid fuel feeding means, the combination of a casing including a bottom and 0p posed side walls, a partition rising from said bottom and extending between said side walls thereby to separate the lower portion of the easing into a receiving part and a delivery part, inlet and outlet connections communicating, respectively, with said receiving and delivery parts,

a rigid wick carrier comprising a top member located above and in the plane of said partition, and side plates depending from said member on both sides or the partition, the carrier having a horizontal slot in the region of said top member, a broad flat wick extending through said slot and down alongside said plates and having its ends secured to the plates adjacent the lower provided with a threaded hole in axial alignment 1 1 with said apertures, a-screw projected downwardly through the first mentioned aperture and threaded through said hole and having its lower 1 end guided within the second mentioned aperedges of the latter, and means accessible from above the casing for raising and lowering wick carrier.

' LEE S. CHADWICTK.

REFERENCES CITED The following references are of record in the file of this patent:

, UNITED STATES PATENTS Number Name Date 1,734,388- Marsh 796,129 Laughton 897,131 Owen 1,488,771 Ainsa 2,082,149 Cheavons 2,213,521 Haeberlin 1,970,880 Bird Aug. 21, 1934 710,928 Winton Oct. 7, 1903 1,349,703 Williams Aug. 17, 1920 2,075,242 Todaro Mar. 30, 1937 353,276 Walton Nov. 23,1886 2,295,799 Focke et a1 Sept. 15, 1942 2,293,697 Chadwick Aug, 25, 1942 23l,730- Rippingille' Aug. 31, 1880 2,086,884 Sherman July 13, 1937 2,253,056 Ullstrand Aug. 19, 1941 2,286,497 Miceli et al. June 16, 1942 Rhind June 1, 1897 the

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