US2412383A - Apparatus for pumping and atomizing liquid fuel - Google Patents

Description

Dec. 10, 1946. w. E. BAKER Q 2,412,383

APPARATUS FOR PUMPING AND ATOMIZING LIQUID FUEL Filed Aug. 4, 1940 v 5 Sheets-Sheet 1 ZSnnentor W/LL/AM E BAKfK.

CIttomeg Dec. 10, 1946. 2,412,383

APPARATUS FOR PUMPING AND ATOMIZING LIQUID FUEL w. E. 'BIAKER 5 Sheets-Sheet 2 Filed Aug. 4, 1940' men 0]. WILLIAM E, BAKER.

(Ittomeg w. E. B'AKER Dec. 10,1946.

APPARATUS FOR l UM PING-AND ATOMIZING LIQUID FUEL Filed Aug. 4, 1940 5 Sheets-Sheet 3 Snvenkgr WILL/AM E, BAKEK.

attorney Dec. 10, 1946. v w. E. BAKER 2,412,383

I APPARATUS FOR PUMPING AND ATOMIZING LIQUIb FUEL Filed Aug. 4, 1940 5 sheets-sheet 4 I I 3nventor W/LuA/w 5 EAKEK.

Gttorneu Dec. 10, 1946. w BAKER v 2,412,383

APPARATUS FOR PUMPING AND ATOMIZING LIQUI'D FUEL ,W/LL MM 5 50x5:

Snoentor after.

Patented Dec. 10, 1946 D STATES PATENT OFFICE APPARATUS FOR PUMPING AND ATOMIZING LIQUID FUEL William E. Baker, Swanton, Ohio Application August 4, 1940, Serial No. 351,356

4 Claims. 1

. paratus, may be divided into three phases: (1)

circulation of the raw oil from a reservoir .to the atomizing equipment; (2) the atomization of the oil involving breaking down and mixing thereof with air and delivery of-the oil-air mixture; and (3) combustion of the oil-air mixture including, as a preferable feature, the addition of so-called secondary air at or in the region of the point of combustion. 7

Each of the three phases of my system includes novel features and, when combined, give a system that permits burning of various grades of fuel oil as will be explained more fully herein- Speaking in generalities, the problem of burning the more highly refined fuel oils is not as dificult as burning of the relatively cheaper grades which are not as well or highly refined. The cheaper and poorer grades of fuel oil heretofore have presented certain difficulties as to pumping, atomization, and combustion which have discouraged the use of such cheaper grades of oil for general domestic and industrial heating, except in those cases where proper and almost constant maintenance could be provided for necpump is provided. That is, the pump system withdraws liquid fuel from the tank or reservoir and pumps it continuously past the metering portion of the pump and returns the unused volume back to the tank or reservoir. While the excess may be controlled as desired, in the smaller type units, I circulate from two to two and one-half times the oil past the metering part of the pump as is withdrawn by the metering pump and di rected toward the atomizing portion of the equipment. In larger units where a greater volume of oil or fuel is consumed, it is not necessary, for satisfactory results, to circulate such a. large excess, although in all cases I prefer to pump from the tank more oil than is required. The reason for pumping the excess oil is to avoid surging, air entrapment, or a deficiency of oil which would interfere with proper operation of the system as essary cleaning and other matters making it possible to use such cheaper grades of oil. A is generally known, in the domestic field, such as oil burning equipment for homes, burners have been designed to handle No. 3 oil.. No. 5 oil is substantially cheaper than No. 3 oil, but the ordinary burner designed for handling No. 3 oil will not give satisfactory service with No. 5 oil because, in addition to inability to handle the cheaper and dirtier, heavier oil, said equipment does not give sufiicient or'proper atomization of the oil. Furthermore, when the ordinary 3 oil burner is furnished with 5 oil, the burner nozzle or tip cokes up in a relatively short time, with extremely unsatisfactory results if not failure of the unit.

Considering first the circulating phase of my system, a combined circulating and metering a whole. Another advantage in pumping this excess 'oil resides in the fact that a continuous, steady supply of oil iscat all times available for the atomizing section during operation thereof. It will of course be understood that fluctuations in the oil supply or presence of air in the line presents a difflculty in holding a. constant-fire. Even assuming that the exact amount of oil could be furnished for any given viscosity, I have found thatthe viscosity of any given grade of oil variesenough to throw any preselected conditions out of balance, so that to safeguard against variations in oil viscosities and the other factors, just mentioned, I consider the pumping of excess oil to and past the metering section to be of vital importance. Itis important not only from the angle of proper operation but also as a safety factor avoiding as it does the possibility of too much fire or too little fire and danger of explosions. As a matter of convenience, it is wise to keep air out of the fuel line because if there is a lack of oil supply, the safety control will kick out, necessitating manual resetting.

Although the circulating portion of the pump handles an excess of oil, measured amounts only are permitted to flow to the mixing or atomizing portion. The pump unit is adjustable to vary not only the amount of oil circulated but also the metering section so that a predetermined measured volume of oil is caused to be pumped to the atomizer.

The atomizer receives the raw oil and causes it to be mixed with a substantially greater volume of air, the resulting mixture being in the nature of a mist or spray.

Especial attention is directed to the fact that the atomizer is so designed and operated that aagiaae's even cheaper,- .heavier grades of fuel oil'can be atomized or converted into a fine mist without so-called preheating to give a'mix which is freely 'is not premixed with air before discl'lalrge from the burner nozzle, but the air used is added at or oil, it has a higher B. t. u. rating per gallon than V "the No. 3.oil and this, coupled with its lower price; is indicativeof the fact that if it can be used, heating costs will be substantially lower.

in the vicinity of the nozzle'.- In my system, the I premixing f the air with oil is an important feature, and the completeness of the premix and the extent or degree of atomization of the oil (even the lower grade oils such as No. is evidenced by the fact that the atomized oil-air mixture can be piped from the atomizer, passed. I

. through a distributor, and fed to one or more nozzles remote from the atomizer itself. This characteristic and the characteristic of the flame itself renders the burning of fuel oil akin to the burning of gaseous fuel. The ability to pipe the oil mist from-the atomizer to some remote point or points increases the field of use for oil burning equipment and the cost of burning oil with my system is extremely favorable as compared to the cost of gaseous fuel,

- Briefly stated, the atomization of the oil accomplished by providing a rotating member having connection with a vacuum inducing means which draws air and oil in proper ratio into space provided within said rotating member. The rotating member and associated parts are of metal andby virtue of their relative movement establishing turbulence, coupled with the presence of relatively high vacuum, the oil and air are thoroughly mixed, with the oil being. broken down .or dispersedinto mist form which can be caused to pass through a bore or tube by means of relatively slight pressure, which is further indication as to the degree and completeness of atomization attained.

- The third phase of the system abovereferred to involves the combustion of the atomized fuel.

The fuel is directed through one or more nozzles,

flow of the secondary air is controlled to give proper relationship with the discharging atom-.

ized oil. More specifically, the air is caused to swirl exteriorly of the oil dischargingfrom the nozzle. The character of the flame itself, whether it be longand narrow or short andbushy, is determined in part at least by the particular shape of the burner tip, pressure applied to the fuelpassing through the burner tip, and direction'of Y movement ofthe atomized fuel as itleaves the burner tip.

For purposes of this application, No. 3 oil will be considered-as representing a high grade, well refined oil, whereas No. 5 oil will be considered as representing thepoorer grade of oil. However, it will of course be understood that fuel oil is used herein by way of example rather than with relation to No. 3 oil. "Because it is a heavier The problem has been to find some satisfactory and reliableway of using the oil.

The atomization of the lighter oils which are distilledis not nearly as dificult as the atomization of the ordinary commercial No. 5 oil which is understood not to be a distilled oil.

For sake of simplicity, as a specific application of my liquid fuel system, I have illustrated and 'will describe its adaptation as a domestic heat-s plant. However, in nosense ofthe word is v the-system restricted to this particular field, as smaller or larger unitscan be made to handle more or less oil per hour. ,The same system can and in some instances, with modified nozzle means, be used for large industrial purposes, en-

gines, and in fact any place where oil burning equipment isat present used and also in new fields where the ordinary oil burning equipment is not satisfactory and where it is customary to: employ a gaseous fuel.

Other objects and advantages of the invention will become more apparent during the course of the following description when taken in connection withthe accompanying drawings.

In the drawings wherein like numerals are employed to designate like parts throughout the same:

Fig. 1 is a perspective view showing a complete unit with the cover removed ready -for association with a-fire box; I

Fig, 2 is a vertical transverse section through one form of'the pumping and metering appa- 'Fig. 3 is a transverse sectional view throughone form of atomizing apparatus; 7

Fig. 4 is a section taken'on line 4-4 in Fig. 3; Fig. 5 is a section taken on lineS-i in Fig. 3; Fig. '6 is a section taken on line-i-Bin Fig. 3 Fig. 7 is a section'taken on line in Fig. 2; Fig. '8 is a section taken on lineil 8 in Fig. 2; 9 is a vertical longitudinal section through ne form of nozzle including means-for controlling theapplication of secondary air; Fig. 10 isa detail of the vane or air directing means arranged around the .nozzle illustrated in Fig. 9;

Fig. 11 is an enlarged sectional view showing Referring to 1, it will be noted that the assembled unit is compact, being carried upon the support 20. A single electric motor 2! is all that is necessary to operatethe equipment, and for the particular uni-t illustrated and about tobe described, a one-quarter horse powermotor is large enough. The pumping and metering .apparatus shown in detail in Fig. -2 is designated in its entiret in Fig. 1 by the numeral 22. The

atomizing apparatus shownin detail in Fig. '3

designated in Fig. 1 in its entirety by the numeral 23. The nozzle and associated parts illustrated,

partially in Fig. 9 is designated in its entirety in Fig. 1 by the numeral 24.

The apparatus 22 and the apparatus 23' are driven by means 01' a, common drive shaft 25 oper-' ated by the pulley 26 connected by means of the belt 21 to the pulley 28 carried by the motor shaft 29; As will be explained later, the atomizing apparatus 23 is operated directly by the shaft 25, while the pumping and metering apparatus is connected to the shaft 25 by gear means contained within the gear box, designated in its entirety by thenumeral 30 in Fig. 1.

The present invention is in no way concerned with any particular electrical control devices. However, I do make use of automatic electrical controls to effect starting and stopping of the apparatus and also to provide'necessary safety means.

Broadly stated, when using the cheaper grades of oil such as No. 5, it is advisable at the start of a .cycle to employ gaseous fuel. Normally, the gaseous fuel is used for less than a moment and, as shown in Fig.1, the flow of gaseous fuel is controlled by means of the magnetic'valve 3|. In those areas where natural or artificial gas'is not readily available, container gas such as Philgas or Pyrol gas can be very satisfactorily employed without inconvenience because the amount of gas required for the operation is quite insignificant.

The normal firing of the atomized fuel after starting by gas is done by means of electrodes, and two electrodes are illustrated and designated by the numeral 32 in Fig. 1. The flow of current to these electrodes is likewise controlled by well known automatic electrical devices.

As an additional precautionary measure, a magnetic type of valve 33 is associated with the raw oil supply line to positively shut off the flow of oil should by any chance dirt or other foreign matter get into the system; Normally, the valve 33 is not required but is installed nevertheless as an additional safety factor; On the other hand, successful operation of the apparatus does not require use of the valve 33.

Beginning first with the oil pumping and metering apparatus 22 in Fig. 1, the raw oil is drawn from the tank through the pipe 34 in Fig. 1, which is also shown i'nFig. 2.

In Fig. 2, the main drive shaft 25 of the apparatus carries the worm 35 meshing with the Worm wheel 36 keyed to the pump driving shaft 45 31 which rotates in the direction of the arrow shown in Fig. 8. In the particular pumping mechanism illustrated and as particularly shown in Figs. '7 and 8, there are four cylinders and a four pistons, each piston, in effect, being two pistons. Each of the pistons, designated in their entirety by the letter A, comprises the portion 38 will have a greater displacement than the head 42, which makes it possible to circulate more oil than can be pumped to the atomizer. The barrel 4!! is keyed to the drive shaft 31 by the key 44 carried by the shaft and received in a slot formed in the barrel. Thereby, upon rotation of the shaft 31, the barrel rotates at the same speed within the bushing 45 pressed into the casing or housing 46. course stationary and are provided with suitable ports through which the oil is received and part i of which is withdrawn by the metering end and pumped to the atomizing section. As shown particularly in Fig. 8, which is a section on line 88 in Fig. 2, the circulating end of each of the cylinders has a the barrel. The oil intake pipe 34 is fastened to the housing by means of a threaded boss 48 communicating with the port 49 extending through the housing 46. The port 49 is disposed in the same plane as the ports 4'! formed in the barrel 4!! and communicating with the closed end of the cylinders 6|. The bushing 45 is provided with a. slot 50 which extends from the point B in Fig. 8 to the point C. As will be explained later,

operation of the pump causes the oil to flow in through the pipe 36 and to fill the groove in the bushing between the points B and C. A second groove 51 formed in the bushing and in the same plane as the groove 50 extends from the point D to the point E as shown in Fig. 8. This groove 5| communicates with the passageway 52 which leads to the valve device 53.

In Fig. 2 is shown the means employed for operating the pistons. Pivotally mounted upon the end 54 of the housing is a thrust bearing 55 pivoted by means of the pin 56 and adjusted about its pivot point by the adjusting screw 51. A hardened ring member 58, having a ball-race 59, is mounted upon the thrust bearing.

Each of the pistons, as shown in Fig. 2, is provided with a hardened end 60. Each of the pistons is preferably made from hardened steel and each has an end 60 adapted for contact with the face of the ring 58. The end 60 of each piston is, broadly speaking, cone shaped to correspond approximately to the operating angle of the disc 58.

The pistons are normally urged outwardly of 50 the cylinder by means of coil springs 6| surand the relatively thicker portion 39. The part I 38 is used for pumping and circulating the oil and the part 39 is used for the metering and 5 pumping of the oil to the atomizing section. The pistons operate in the pump barrel 40. The cylinders ll formed in the barrel have a bore, a portion of which is of greater diameter than the other portion; that is, the end of the ing the part 38 of the piston A is of less diameter than that part of the bore receiving the piston end 39. In the apparatus illustrated, the diameter of the end 38 is approximately three-eighths of an inch and the diameter of the end 39 is approximately seven-sixteenths of an inch, which produces the shoulder 62 employed as a cylinder head'of annular formation to take care of the metering and pumping of the metered oil to the atomizing section.

Roughly speaking, the cubic displacement of the end 43 of the piston is approximately two to two and one-half times the cubic displacement of the annular head 62 and, as the two pistons operate to ether, it will be seen that the end 38 bore receivno rounding the pistons bearing at one end against the cylinder barrel and at the opposite end on the flange 62, preferably formed as an integral part of the piston.

- As shown in Fig. 2, the left hand piston is in its wide open position and the right hand piston is in its closed position. v

To facilitate rotation of the cylinder barrel and associated parts, a roller bearing unit 63, illustrated in Fig. 2, is placed between the bushing 64 pressed into the end of the housing, serving as a sleeve bearing for the shaft 31 and the flange 65 formed at the end of the cylinder barrel.

The opposite end of the drive shaft 31 has a detent 56 receiving the spring-pressed ball 61 having in operative relationship therewith the coil spring Eli seated in the cavity 69 formed in the end 53 of the housing,

The main function of the .ball and detent construction is to assist in holding the oil seal parts together so that the oil seal, designated in its entirety by the numeral it, will function properly. As shown, a second spring H is effective upon the opposite end of the oil seal to likewise assist in holding the parts together, and the combined The housing and bushing are of port 41 extending outwardly through with the needle valve 11. close fit through the bushing 18 and is such as to prevent oil leakage between the stem and,

"aliases v action of the two effectively pr D 8 Q I oil through-the oil seal.

Upon rotationof the shaftfll, the barrel is rotated and as the ring 58 is mounted in an m clined position, it will be seen that the pistons are caused to work in and out of their respective cylinders. 7 The pump isso timed that as each cylinder is moved past the groove 50, oil will be drawn into said cylinder. Then, upon continued movement of the barrel in the direction of the arrow in Fig. 8, each cylinder will be taken out of communication with the groove 50, slid past the land F and then brought into communication with the second groove In the meantime, as the piston is riding onthe ring 5-8 forming an effective cam, it is moving within its cylinder and, when in communication withthe groove 5|, each piston GtothepointH inFlg. "I. the intake groove of the metering section and unused oil turndtothetank'.

flows through the exhaust pipe 88 and i The so-called metering operation ishandled by the thicker diameter portions of the pistons previously'referred to asthe parts 39. The parts example, as shown in Fig. 7, the. top cylinder of the figure is in communication with the groove is at that partof the stroke causing forceful movement of the oil into the groove and'through the passageway 52,-and into the control valve assembly '53. It will of course be understood'that each of the pistons, for example four, goes through the same cycle as the others, so that each of the individual pistons serves first/to draw oil into the pump and each serves to force part of the oil intothe valve-53.

In Fig. 8 the valve operating mechanism has been. removed for sake of clarity. -By comparing Figs. 2 and 8, it will be seen that the oil being pumped through the passageway 52 is received in the cavity 12. Mounted within the cavity 12 is abellows type .valve 13 carried by the screw cap 14 threadedinto the end of the opening. as shown. The bellows valve carries the stem 15, at the opposite. end of which is a self-aligning head 16 designed for cooperation bushing. However, there is sufficient clearance to permit reciprocation of the stem through the bushing, movement thereof being controlled by the oil itself acting upon the bellows valve.

When the unit is not in operation, the valve is closed. At the start of a cycle, the pump pumps the oil into the cavity 12, as has already been explained, and when adequate pressure has been built up, normally about two pounds per I square inch, the bellows valve is compressed; that is, the end remote from the cap M is moved toward the cap which slides the stern through the bushing and lifts the end 16 from the valve Upon such movement of the'valve, the port The stem 15 has a 19 formed transversely-through the stem'is moved beyond the end 8d of the bushing 18 and is thus brought into position where it may receive oil from the chamber 12, The. stem is also provided with a second transverse port 8 l disposed beneath the port 19 and the center of the stem is removed so that the two ports are in communication with one another through the passage 82 as shown in Fig. 2.

Thus, theoil flowing into the port 19 passes through the channel 82 and into the port 8|. I

Shown particularly in Fig.7, the port 8| registers with the port 83 extending through the bushing and into the channelway 84. The oil then flows through this port into the conduit 85 formed through the bracket 86 which is a part of the pump housing, as clearly shown. The oil thus passes to the metering portion of the pump going into a groove 8'! formed in the bushing 45, which groove extends from the point 3-! of course 'operatein the enlarged end of'the cylinders and each enlarged end has aport 89 extending from the cylinder outwardly. For

81 formed in the bushing.

It will be understood that the flow. of oil through the passageway '85 and groove 81 is induced by the pumping end 38 of the pistons As each of the metering portions of the cylinders is in registration with the groove 81 some. of

the oil into the cylinder, depending, of course, upon the stroke of the piston which in turn is dependent upon the "adjustment of the thrust bearing and ring previously described. 'As the cylinder barrel is rotated in the direction of the arrow in Fig. 7, the oil "is drawn into the cylinder and is discharged therefrom-in a groove 90 disposed in the sleeve between points J and K. The groove 80 is inthe same plane as the groovell. It willbe noted that thereis a land between the points G and K. The oil discharged from each cylinder and received in the groove 90 is then caused to flow through the passageway 9| shown in Fig. 7 and. thus con-'- veyed or forced into the cavity 92 clearly illustrated in Fig. 2. By further reference to Fig. 2,

it will be noted that a cylindrical filtering screen 83 surroundsthe bushing-18 so that oil coming from the meteringpump is caused to passthrough the screen and into the orifice 94 extending transversely through the bushing.

When -the unit is not in operation, the selfaligning end 16 of the stem seats upon the needle valve 11 so that no flowing of oil is permitted to g0 through the conduit 95. However, when operating, the oil coming from the metering portion of the pump is received-within the cavity 92, passes through the screen and into the orifice 94. As previously mentioned, during pumping, the bellows valve has been caused to slide the stem so that the needle valve is opened and the oil permitted to "flow through the bore 95 of the conduit 95 and onto the atomizing section,

When the unit cuts off and the pressure is relieved, the bellows valve slides the stem and associated parts in the opposite direction, which returns the port 19 to within the bushing, preventing further flow of oil therethrough and,

likewise, the needle valve I1 is closed so that stant and measured amount of fluid is desired.

It is important that the two pistons produced by having a single piston with different diameter sections be used, because in this way they have the same'stroke and with no opportunity for one piston gettingout of balance with the other. The ratio of pumping capacities is fixed by the relative displacement between the two sections and,

9 in the particular illustration herein made, the displacement of the pumping piston 38 is from two to two and one-half times that of the displacement of the metering piston 39.

With this arrangement and control of ports and .use of the bellows valve, a constant excess supply of oil is at all times moved through the In operation, air is drawn in from bothfends of the atomizer housing between the shaft and the housing flanges I08. The air intakes are designated by the letter M. At the left hand side of Fig. 3, the air passes through the channel I09 into the enlarged part of the casing whereas,

port, from which the metering valve draws its measured supply of oil during operation of the apparatus. The same ratio between pumping of raw oil and metering is maintained, for, as the cam ring 58 is adjusted to furnish more or less oil by the metering device to the atomizer, a corresponding increase or decrease of oil is pumped by the pistons 38.

Because of the presence of an abundance of oil in the groove 81, there is always more oil present than can possibly be drawn into the metering cylinder during the time that any given cylinder is in registration with said oil groove.

Although the metering pumps discharge the vice indicated generally by the numeral 23 in Fig. 1, reference is made to Figs. 3, 4, 5 and 6. The conduit 95 carrying oil from the metering device has connection with the atomizer as shown in Fig. 4, being threaded into the housing 97. Extending through the housing 91 is the passageway 98.

The main shaft 25 has an enlarged portion 99 provided with both oil and air grooves or slots. As shown particularly in Fig. 3, the shaft 25 is mounted upon the bearings I00 and IM disposed approximately at both ends of the housing 91.

Although any number of cylinders andpistons can be used, depending upon the size of equipment,'I prefer a minimum of four cylinders to insure smooth operation. In the design illustrated in Fig. 3, four cylinders are employed which are, in effect, double cylinders as tandem or opposed pistons operate in each cylinder, thus at the right hand end of Fig. 3, the passageway H0 is provided for passage of the air into the enlarged part of the housing. The air thus admitted to within the atomizing housing is directed to the air grooves III through the opening II! as shown particularly in Fig. 6. As a matter of fact where the opposed piston construction is employed there are two conduits II2 communicating with the air groove III, one at each end of the enlarged part 99. The enlarged part 99 is a rotating valve operating in the cylinder defined by the wall I I3 which surrounds it. This is the part of the apparatus wherein the oil and air is mixed to give an atomized mixture. The air is drawn into the groove HI because of the suction which is created upon reciprocation of the pistons I02 and I03. As shown at the top of Fig. 3, the two pistons are at their closest appreach in their cycle. As they are caused to separate, a vacuum of relatively high proportions is created and the cylinders through the port IIA communicate with the air groove in the atomizer part 99 of the shaft.

Likewise, the enlargement 99 is provided with the oil groove II5 which encircles the valve and communicates with the air groove at the point N. The suction or vacuum created by operation of the pistons draws oil through the conduit 95,

opening 98 and into the oil groove II5. An important feature of the arrangement of the air groove is that it is so located that there is no opportunity for centrifugal force or other factors to prevent proper movement of the oil and air. For example, if the air groove I II continued entirely around the valve as a circular groove, centrifugal force would be such in many cases that the oil would stay in the groove and not flow out of it. However, by carrying the groove almost entirely around the valve by bending it away-from the closed end 6 and causing it to run obliquely as at H! to joinin the forming of an arrowhead as at H8, this tendency toward oil pocketing or accumulation is entirely avoided.

The normal speed of rotation of the shaft and atomizing valve is from 1000 to 2000 revolutions necessitating eight pistons for the four cylinders.

In Fig. 4 the cylindersare indicated by the letters L, and in each of these cylinders is mounted for reciprocation the opposed pistons I02 and I03. The movement of each individual piston is induced by a cam ring I04 connectedto the shaft 25 through the radial thrust bearing I05. The angular mounting of the cam rings is quite clearly illustrated in Fig. 3 and, in this particular instance, there is approximately a '7 degree angle,

per minute. While it can be operated at still greater R. P. M.s, to insure long life, operation and this can be varied one way or another d..-

pending upon the capacity of the unit.

Each pistonis urged outwardly of its cylinder by spring means I00 encircling the same exteriorly thereof and contacting with the end flange I01. Likewise, each piston has a contact button of hardened steel for riding upon the cam ring I04 which is also of hardened steel or some other wear-resistant metal.

Upon rotation of the shaft 25, the cam rings will act upon the pistons to cause them to be forced inwardly of the cylinders and, as the low part of the cam passes the piston, the spring will cause it to be withdrawn.

within this recommended range is desired.

The width of the air channel or groove is approximately inch and the depth approximately inch. On the other hand, the oil groove or ring I I5 is but inch in width approximately, and about inch deep.

The atomization of the oil takes place, in themain at least, while the oil and air is still within the grooves hereinabove referred to as the air grooves. At least I feel confident, based on my observations, that the major part of the atomization does so take place. This is undoubtedly due to the turbulence induced by the rotation of the shaft and mixture with a preponderance of air present as compared to oil coupled with the fact that this action or mixing taking'place in a vacuum or partial vacuum created by the pistons. The fact that the valve member is rotating at a relatively high speed within its cylinder may also contribute in a mechanical break down of the oil, so to speak, further assisting in getting extremely fine atomizatio of the oil in the air.

. l1 4 The mixture so formed is of course drawn into the cylinder between the pistons, although in, the typeof construction where a single piston operates in a cylinder suitable ports are arranged in the closed end of the cylinder. In any event,

the atomized fuel is drawn into the cylinder by the action of the piston and is then discharged by-contlnued operation of the piston through the I port H9 and through the bore of .the shaft indicated by dotted lines I20 in the direction of the arrow to the right of Fig. 3. The bore I20 is also illustrated in dotted lines in Fig. 5.

In operation, the metering pump furnishes oil a to the conduit "with sufficient pressure to get the oil to. the'atomization unit, but positive handling of the oil within the atomization unitis vobtained -uponoperation of the pistons within the unit itself. I

f The vacuum created by the pistons in the atomlzin'g device draws in air from outside of the housing, the air being drawn first within the housing and then through suitable openings through the cylinder web into the atomizing valve. The enlarged part 99 formed on the shaft may be broadly referred to as the atomlzing valve.

Thus, as stated, the suction or vacuum created by the pistons induces a forceful flow of air into i the so-called air groove formed in the circumference of the atomizing valve. The air channel follows a tortuous path and, in the particular design illustrated, there are two of such grooves which come together in the form of an arrowhead. The passage of air through these passageways is sufficient to induce a ,fiow of oil through the circumferential groove 5 with the oil entering and mixing with the air in the air grooves.

The turbulent action carried on in the presence of sub-atmospheric pressure-is sufficient to positively atomize or mistify the oil even when the oil is relatively heavy such as No. 5 fuel oil.

The extent of atomization may seem amazing considering the relatively simple manner in which it is accomplished,,but the extent to which the atomizing of the oil is accomplished is evidenced by the fact that-the atomized fuel can be burned much in the same way as can ordinary gaseous fuel, including the piping-thereof after atomization.

Continuing with the operation, the atomized mixture is drawn into the cylinder and discharged into the exit'port and through the bore I20. It will be understood, of course, that the amount of oil provided to the groove or oil cavity H is determined by themetering pump previously de- -scribed. Especially in the larger installations where very substantial volumes of air are'drawn oil burning equipment'as well as in other'places.

communication with the firebox of a furnace, and Fig. 9 is an enlarged detail of the nozzle and associated parts in such a type of installation. In this case the nozzle, designated in its entirety by thenumeral I. is securely mounted upon the end of the shaft 20 by means of the coupling. I22.

Although the invention is not restricted to any specificform of nozzle, as the atomized fuel is of such caliber that it can be employed with many different kinds of nozzles and burned like gaseous f fuel, nevertheless, where an installation is made and subject to periodic starting and stopping, it

is extremely important that a properly designed nozzle be used to'avoid unnecessa coking and o'thertrouble's. The particular nozzle illustrated in Fig. 9 is extremely eifllcient for ordinary home Part of the'nozzle is shown in section in Fig. 9 for purposes of illustration. The nozzle comprises the barrel I23 screwed upon the shaft I24 to permit easy removal thereof and cleaning when necessary. Mounted within the barrel is a springpressed insert I25 normally'urged toward the outer end of the nozzle by the coil spring I26.

The insert has a'longitudinal bore I21 extending longitudinally through the intake portion thereof, the atomized fuel passing from within the insert outwardly'through the transverse openings I28. The-atomized fuel is then located between ,the exterior of the reduced part of the insert and the inside surface of the harm] or in the passageway I29. A cone tip I30 is formed at the outer end of the insert and curved, spaced vanes I3I maintain the insert in position to insure a flow of the atomized fuel entirely around the tip. The curving of the spacers induces a mild swirlin action as the atomized fuel passes through the orifice I32 formed at the extreme outer end of the nozzle.

into the unit, it is preferable. that the air be v passed through a suitable filter to prevent contamination of the atomizlng device. On the smaller units, such as the one illustrated, the clearance-between the housing and shaft is sufll- It has been my experience that if the nozzle is mounted at the wall of the combustion chamber, some coking results by reason of the fact thatwhen the unit shuts oil, the heat in the combustion chamber is excessive and has a deleterious effect upon the burner.

To overcome this objection, I mount the nozzle in a position spaced from the combustion chamber, making use of a flared refractory shield I33 which may be carried within a metal frame I34. The mouth of the flared portion or end I35 ha a diameter sumcient that the flame will not strike it. However, the distance between the end of the nozzle and the end I36 of the shield should be a minimum of about three inches. This placement of the nozzle, a minimum of three inches from the combustion chamber, is sufficient to prevent coking of the nozzle as has been definitely demonstrated and P q in actual In this construction, secondary air is used and the housing or casing I34 can be'formed to also house a blower I31. This is an ordinary air prociently close and the action of the rotating shaft such that in practice no troublesome dirt enters the system. r

What is done with theatomized fuel as it leaves the atomizing unit is dependent upon the use to which it is to be put. Ina domestic heatingfurnace installation, the burner nozzle may be mounted directly upon; the end of the shaft 25, whereas in other cases the atomized fuel may be passed to a distributor and then furnished to a plurality of burners at p ts.

The unit shown in Fig. 1 is a complete installation capable of being mounted in operative some remote point or around the nozzle and in spaced relation thereto (see Fig. 9). This vane member I40 can be constructed of metal and fitted against the inner surface ofthe refractory lining I33, The individual vanes I are curved so that when the sec- I I I is being put, but in all cases where secondary air I is employed, I prefer that the swirling action be resorted to because a more satisfactory flame is obtained than when the air merely flows in absence of swirling.

In Figs. 11 and 12, I have illustrated one form of distributor which may be used where the atomized fuel is to be piped or supplied to a plurality of burner nozzles. In the construction of Fig.

9, all of the atomized fuel is consumed by a single nozzle, and this may be referred to as'a direct burner unit.

In Figs. 11 and 12 the fuel is divided and sup-- plied to more than one nozzle and this may, broadly speaking, be referred to as a remote supply type of apparatus. The shaft 25, through which the atomized fuel is carried away from the atomizer, carries on its end the distributor head rotor I42. The rotor has the cavity I43 and a port I 44. The distributor cap I45 is carried on the stationary support I46 and may be provided with a plurality of pipes I41. In Fig. 12, four of such pipes are illustrated. Suitable sealing means I48 is employed to prevent oil leakage. Upon rotation of the rotor, which of course is at the same speed as the speed of the atomizer, the atomized fuel will be intermittently supplied to the plurality of pipes, that is, during the time that the port I44 is in registration with each pipe. It might seem that by not providing a continuous flow of fuel, the burners furnished by each pipe would fluctuate, but this is not the case.

The main reason for providing a distributor of this kind is to prevent settling out of the oil from the atomized mix which might happen if a large volume of the mixture were permitted to stagnate in a conduit. I have discovered that where the mixture is fed intermittently as by the rapidly rotating rotor head, a constant supply of fuel mixture is furnished to each of the plurality of burners without settling out of the oil and without interfering with constant, even combustion.

In some types of oil burning equipment, the requirements are such that aburner capable of handling large gallonage per hour is required. In other cases, 'it is extremely desirable to have a burner which will operate efllciently with very small oil consumption per hour. has not been considered practical to operate oil burners, especially with such grades of oil as No. 5, on anything less than about two and one-half gallons per hour per burner and as a rule it will run higher, perhaps three or four gallons per hour per burner. With the more highly refined oils, the best that has been done heretofore has been a burner capable of operating with a minimum of about five quarts of oil per hour. It will be understood that I do not Wish to be considered as saying that no one has been able to do better than this in a laboratory way, but with the commercial equipment capable of giving reasonably satisfactory results, the above approximate figures are correct.

This point is made because with the equipment above described, I have been able to fumish-four burners, each burner consuming but one pint of oil per hour and this was No. oil of standard commercial grade. Not only this, but the atom- Heretofore, it

ized fuel in one installation was passed from the atomizer through tubing having but a one-quarter inch bore for a matterof twelve to fourteen feet before reaching the nozzle, and the flame of each of the four burners was quite similar to the ype of flame obtained when burning natural as.

In the smaller installations, secondary air may be used, but in some cases its use may not be required and in any event good combustion will result even when there is no secondary air forcibly applied by means of a blower.

Although four conduits are shown in Fig, 12 intended to supply four different nozzles, it will be understood that a greater or lesser number of nozzles can be furnished. In thiscase, of course, the total capacity of the plurality of burners would have to be properly related to the atomizer which in turn would have to be furnished with oil by a properly related pumping and metering device. These factors will be readily appreciated by those versed in the art.

It will be noted that in both the pump and atomizing unit. four cylinders have been illustrated. There is nothing critical about the number of cylinders and pistons which can beemployed. Aspreviously stated, the use of four cylinders has proven desirable as a minimum because a uniform, even flow of material is obtained. However, as units ofincreased capacity are made, it is preferable to'increase the number of cylinders and pistons to get the desired added capacity. This is preferable to merely increasing the diameter of the-cylinders. I have personally constructed units with sixteen cylinders for forty gallon an hour burners, and if still larger units are desired the number of cylinders can be .further increased, The same princi les and same mode of operation are used with the larger units as are us d with the unit com letelv described in detail in this application. In the main. the workin parts are lubricated by the fuel itself. but it will be understood thatexternal shafts and parts which do not come in contact with the fuel can be lubricated in theordinary manner.

Included amon some of the obiections in the art to the use of No. 5 oil, especially for domesticpurposes, are the matters of dirty fire. incomplete combustion, coking, and stoppage from firefluctuations. I believe that most of these difficulties have been due to improper and inadequate atomization of the fuel, and perhaps also improper delivery of the atomized fuel to the burners.

Another difliculty encountered has been bleeding of the lines or the system, permitting air to enter which may result in a throw-out of the safety device or failure to gain ignition.

The danger of bleeding is overcome in connection with the pump because when the bellows valve closes (Fig. 2), it traps the fuel supply 011 in the line, so that the line is always full of oil.

A further factor that is of considerable importance, especially when handling No. 5 oil, resides in the fact that with my apparatus, if the electric power fails, causing stoppage of the unit, and the power is resumed again while the fire box is still hot, there is no danger of explosion because the fuel is in such a finely divided atomized state that it will ignite even if the gas lighter is not on. With prior devices, with which I am familiar, the atomized No. 5 oil has been insufficiently atomized to respond properly under such circumstances, and if the gas pilot is not ignited when theoil is thrown into the combustion chamber,

- A 15' there is .grave danger of explosion because of delayed ignition and undue accumulation-of fuel.

I have previously explained that even with a cold furnace, the gas pilot is left on for less than a minute before the electrical ignition is adequate to handle the vaporized oil. "This is a further indication of the extent to which the oil is atomized auasas" groove and said deliverypassageway into successive communication with each one of said second mentioned cylinders through their respective ports, and means for reciprocating said pistons in Y timed relation to the rotary movement of said atomizing valve to cause each of said-pistons to with my equipment. .As a result of this flne at- =omization, I get a clean fire, freedom from coking, uniform fire and general low cost of operation,

and can get these results with any grade of fuel without preheating or other conditioning of the oil prior to its pumping into the metering part of my apparatus. I

It is to be understood that the form of the invention herewith shown and described is to-be.

atomization of liquid fuel, a rotatable atomizing valve having an air passageway offset with respect to the axis of rotation of said valve and extending at an angle other than a right angle to its path of bodily movement and a liquid passageway intersecting said air passageway at an angle other than a right angle, meansfor providing a measured and constant supply of liquid to said liquid passageway, means associated with said valve for setting up a flowing current of air through said air passageway to draw liquid from said liquid passageway into and mix it with the current of air, means for rapidly rotating said valve while the flow of ai through said air passageway is maintained to produce a turbulence of the air and liquid'to disperse and atomize the liquid so that it will be conveyed b the air as a mist, and means for delivering the a omized fuel from said atomizing valve.

2. In apparatus for the transmission and atomization of liquid fuel, a housing, a cylinder within said housing, a rotatable atomizing valve operable within said cylinder and having a circumferentially arranged air groove extending in a tortuous path, an annular liquid groove of relatively smaller capacitythan the air groove opening into said air groove and a delivery passageway leading from said valve, means for providing a measured and constant supply of liquid to said liquid groove, a plurality of cylinders surrounding said first mentioned cylinder and each having a port communicating with said first men-- tioned cylinder, a piston operable within each of said second mentioned cylinders, means for rapidly rotating said atomizing valve'to bring said air oil which is flowable atzero degrees Fahrenheit be in its suction stroke, when its-respective cylin-- der is in communication with-said air passageway to setup a flowing current of air through said air passageway and to draw liquid from said liquid passageway into said flowing current Of air and in its compression stroke when its respective cylinder is in communication with said delivery passageway to deliver the mixture of atomized liquid and air from said atomizing valve.

3. In apparatus for the transmission and I atomization of'liquid fuel, a cylinder, a. plurality of cylinders arranged around said first mentioned cylinder and each of said second mentioned cylin- 'ders having a port communicating with said first mentioned cylinder, a pair of pistons operating in each of said second .mentio'ned cylinders oneat each end thereof, means for reciprocating each pair of pistons toward and away from one another within their respective cylinder, a rotatable atomizing valve operating within said first mentioned cylinder, said atomizing valve having an annular liquid groove inthe outer surface thereof remote from said ports and also an air groove which crosses the liquid groove and follows a tortuous path, means for rotating the atomizing valve to bring the air groovetherein into communication with said cylinder ports. during part of such-rotation and out of communication during other parts of such rotation, said air groove being adapted to be 'incommunication with at least one of said second mentioned cylinders at all times but only when' the pistons therein are creating a suction by moving away from one another, and a conduit for receiving the atomized liquid from said atomizing valve.

4. In apparatus for the transmission and atomization of liquid fuel, a cylinder, a rotatable atomizing valve operating with'insaid cylinder, 9.-

winding air groove in the outer. surface of said valve, means associated with the atomizing valve for setting up a flowing current of air through said air groove, a'liquid groove in the outside surface of said valveintersecting said air groove at a point intermediate its ends for introducing a stream of liquid into' the flowing current of air within the air groove, means for rapidly rotating said valve while the flow of air through said air groove is maintained to produce a turbulence of the air and liquid to disperse and atomize the liquid so that it will be conveyed by the air as a mist, and means for delivering the atomized fuel from said atomizing valve.

WILLIAM E. BAKER.

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