US1724373A - Oil burner - Google Patents

Description

Aug. 13, 1929; H. .L SAUVAGE OIL BURNER y Filed oct. l25, 192e v sheets-sheet 1 v Aug. 13, 1929. H.. L SAUVAGE 1,724,373

OIL BURNER Filed oct. 25, 192e 7 sheets-Sheet 2 .BO/Lil? WEA?. STACKIFA/V JO7 8 g 7'0 BURNER M0 TOE 7&1 206 l J c UNE r/ffmo.:

PAW/VE 517/7225/ Aug. 13, 1929.

H. 'J. SAUVAGE OIL BURNER Filed Oct. 25,4 1926 7 Sheets-Shevet- 5 Aug'. 13, 1929.

H. J. SAUVAGE on. BURNER Filed oct.. 2S, 1926 'l 7, Sheets-Sheet 4 Aug. 13, 1929.,

H. J.' SAUVAGE on. BURNER Filed Oct. 25, 1926 '1 sheets-sheet 5 qkm, l NM1 Aug 13; 1.929. H. J. SAUVAGE 1,724,373

v oIL BURNER Filed Oct. 25, 1926 '7 Sheets-Sheet 6 Patented ug. 13, y 1929.

UNITED vs'rirrEs 4 1,724,373 PATENT OFFICE.

HERBERT J.l SAUVAGE, or CHICAGO, ILLINOIS, AsSIGNoE 'ro DRYING SYSTEMS', INC.,

or CHICAGO, ILLINoIs, A CORPORATION or ILLINOIS. f

OIL BURNER.

Application filed October 25, 1926. Serial No. 143,966.

This invention relates to oil burners and the part-icular illustration vshown in the drawings is use ful for domestic heating purposes.

Heretofore it has been customary in this art, when rotating cups werev employed for atomizing the liquid fuel, to drive these cups either with universal motors which are unreliable in certain respects, or to dr1ve the cupsat a speed corresponding to the normal speeds of induction motors when on standard circuits of sixty cycles. The atomization of the fuel is not etlicient under these conditions,

mainly due to'the insuilicient speed of rotation of the atomizing cup,"and more efficient atomization was sought by enlarging the size of the rotating cup. When a universal motor is employed it gives considerable trouble, due to the use of al commutator and brushes, and also it is quite variable in speed, because of the differences in load and slight changes in voltage of the currentldriving it.

These andvarious.. other disadvantages heretofore encountered are overcome by my improved form of 'oil burner', and highly efficient atomization of the fuel oil is attained by rotating my small atomizer cup at a relatively high and uniform speed. This is accomplished by having my pump motor drive a high-frequency generator, preferably 180 cycles, the current from which in turn drives a two pole induction motor at approximately 10,300 R. P. M. The fuel atomizing cup is mounted on the shaft of this induction motor, and its extremely rapid rotation givesa very thorough and eflicient atomization to the liquid fuel.

Further objects of this invention are to overcome certain operable limitations in the mechanical and electrical arrangements generally of fuel atomizing units; and to provide improved and simplified electrical controlling means for oil burners and fuel supply means, which willinsure safe operation under widely differing conditions.

Another object accomplished by this invention is in the provision of means for alltomatically cutting oft' the current from the pump motor in case fuel is not supplied to tl1 e burner, or if supplied thereto, is not ignitedfsotlsthe'heat' from theproducts of combustion is not raised .to-a predtermined degree within a predetermined length of time. l A still further object of this invention is to provide safety means for breaking the motor circuit in case the stack thermostat switch becomes blocked in one of its posi.- tions so that it can not return to its initial position upon the cooling of the stack.

An illustrative embodiment of this inventionis shown in the accompanying drawings, in which v 'Fig 1 is a view in perspective illustrating the general arrangement of a complete installation of oil burner and' operating means therefor..

Fig. 2 is a diagram showing the electri- (fzally controlled means and the circuits there- Fig. 3 is a vertical sectional view of the fuel atomizer induction motor and resilient means for mounting the motor.

Fig. 4 is atop plan view of the structure as shown in Fig. 3.

Fig. 5 is a sectional view taken on a line 5-5 of Fig. 3, showing a damper for controlling the flow of air 4through the burner.

Fig. is a sectional detail taken on the line 6 6 of Fig'. 3 with the motor housing removed, showing the three point suspension mounting of the motor unit.

Fig. 7 is a front elevation, partly in section, illustrating the' arranagement of the motor, and generator set and fuel pump driven thereby.

Fig. 8 is a vertical sectional view taken on the line 8-8 of Fig. 7.

Fig. 9 is a sectional v iew taken on the line 9-9 of Fig. 8.

Fig. 10 is a fragmentary View illustrating the valve arrangement of the pump.

Fig. 11 is a view in perspective illustrating one of the valves.

Fig. 12 is a section taken. on the line of 12-12 of Fig. 15, with the parts in normal operating position. V v

Fig. 13 is a view of the same with the contacts open.

Fig. 14 is a view of the same with the parts being restored to their normal position.

fFig. 15 is an enlarged detail in elevation of a safety means for controlling the burners circuit.

Referring to the drawings, Fig. 1 illustrates a househeating unit in which a furnace l isv provided withthe improved oil burner, the atomizing unit of w-h1ch is indicated at 2.

. The motor 3 of this atomizing unit-.receives its current from a generator 4: driven by a l 11, provided with springsl 12, supporting motor 5.

centering pins 13 upon which rests the motor frame 14. This resilient mounting secures a very quiet operation of the atoinizing unit. as the springs 12 absorb the vibrations of the motor, which otherwise would be transmitted to the floor of the furnace room. The frame 14 carries the field 15 of the motor and provides bearings 16 and 17 for the rotor shaft 18, the rotor being indicated at 19. A hood 14a of inverted funnel shape is secured to the top ofthe motor frame 14 for keeping dust and dirt out of the motor.. The rotor shaft 18, is housed between the bearings 16 and 17 fort-he purpose of carrying a lubricating oil froln'the oil container 20, upwardly to the bearing 17. This lubricating yarrangement is specifically described and claimed in applicants co-pending application for patent Serial No. 124,179, tiled July 23, 1926.

The rotor shaft 18 carries a vertically disposed co-axial shaft in the form of a straight rod 21, which has'a reduced portion 21' for imparting flexibility thereto, and is located adjacent the lower end of the rod 21, so as,

to utilize such flexibility for permitting the upper end of the shaft to secure a center of rotation under the gyrostatic effect of high speed. The shaft 21 supports anatomizing cup or revolvingnozzle 22 on its upper end,

, a fan 23 is attached to the cup 22 for deliverlng a current of air which assists in atomiz- CII ing the fuel. Additional air for supportingv combustion passes upwardly around the atomizing unit through an air baille 24. Fuel is supplied to the atomizer 22 by gravity from reservoir 37 in housing 6through conduit 25,shut-of valve 25 and low-regulat-' ing valve 25". The conduit 25 is closed at lts discharge or nozzle end except for a restricted orifice 26 at the side of the end of the conduit which faces the direction of rotation gf the cup for directing fuel oil into the atom1zer in the direction of the rotation thereof. This arrangement of fuel discharge to the cup gives a very even and steady flame. The atomizing cup 22 is provided with a flange 27 of ring form surrounding a collar 28 at the lower end of the cup, and having 1ts outer' edge spaced slightly froml the inner wall of the cup 22. The purpose of the flange' 27 is to receive the fuel oil discharged from the aperture 26 and direct it by the shortestpossible path Yto the inner wall of the atomizer cup. The space 27 between the flange 27 and the bottom 29 of the cup is serviceable in collecting the few drops of excess fuel'which could be delivered to the atomizer when coming to rest after an operation of the burner. The cup 22 is supportcd coaxially upon shaft 21 by a spider 30 secured to the shaft by the nut 31 clamping the spider between it, and a collar 32. The

l.spider 30 also supports through spacers 33,

a cover plate 34 for the atomizer which is spaced from the upper edge of the atomizer only slightly to provide the annular outlet 35 for the fuel. dust from settling into the cup and likewise it prevents any downward draft through the cup toward the fan 28 and the cup thus remains free from carbon deposit. The purpose of the baille 24 is to separate and deflect the air uniformly outwardly in correspondence. withthe'direction of the flame from the burner. Ignition is effected by means of agas pilot burner indicated at 36 in Fig. 3.

This plate serves to prevent Regulation of the amount of air passing up throughthe aton'iizing unit is controlled bya damper which comprises a plate 24'1 provided with openings 24h, and a shutter 24C, arranged to rotate relative to the plate 24H. Shutter 24C is provided with openings, disposed so as to register with the openings 24" when in one position, and to be entirely out of registry when in another position. A variable amount of air is thus secured, depending upon the positioning of the'shutter 24C. y The fuel pump illustrated in Figs 7 to 11 serves to draw fuel from the supply tank upwardly into a fuel chamber reservoir 37, Fig. 7. The chnmber 37 is providedwith an over-flow connect ion 37 back to the supply tank at the threaded aperture 38, therefore the chamber 37 only holds sufficient fuel to insure a. fuel supply to the atomizer upon starting operations during the time that the pump becomes primed. The fuel flows from chamber 37 through the'outlet 39 to conduit 25 shown in Fig. 3. The

outlet 39 is normally closed by a valve 4() which is governor operated so that it is automatically opened only when the motor 5 has attained a predetermined speed. The shaft 41 of vthis motor carries at its right hand end Fig. 7. a centrifugal governor 42 arranged to rock to the right a.. bell crank lever 43 around its pivot 44 and an arm 4 5 for the purpose of filling chamber 37 when no fuel is available .to operate the thermal switch 1n the combustion chamber. B v this manual operat10n of bell-crank qlever 43 the valve 40 may be allowed to remain closed against the action of governor 42 whlle 4 chamber 37 is being filled by the pump. The

bell-crank lever 43 is operated in this manner by drawing upwardly on knurled knob 49 on the top end of a rod 50 which, at its lower end is provided with a collar 51 for engaging the outer end of arm 48. In such an operation of rod 50 the circuit through the mot-or 5 is closed independently of the stack switch 52, relay 80 and electrically heated thermostatic element 94, the rod 50 being provided witha contact element'53 mounted upon an insulating block 54, which j with said trough for carrying any such leakage to the reservoir 37. The inlet and outlet ports for the cylinder of the pump are indicated in Figs. 7, 8, and 10. The fuel is drawn from a storage supply tank to the pump through a conduit 61, Fig. 1, leading to a tubular strainer 62, Fig. 7, the conduit 61 being threaded in the aperture 63 in the head of the pump. From the interior of the tubular screen 62 the fuel is drawn through an intake port 64 to the cylinder of the.

pump by the down stroke of piston 57. The port 64 is controlled by a disk valve 65 which closes the port upon the up stroke of thepiston. The fuel in leaving the cylinder, passes through an outlet port 66 similarly valve-controlled to a conduit 67 which serves to conduct the fuel to the reservoir 37, Fig. 7. The housing 6 for the fuel pump is divided by a partition Wall 68 separating the fuel reservoir 37 from chamber 69 whichv contains a lubricating oil for the pump, gears, and governor. Rapid rotation of the worm throws lubricating oil up an inclined wall 70, Fig. 8, into a trough 7 O, which conducts the oil to bearings 71 and 72, Fig. 7.

The electrical controlling means for the oil burner as diagrammatically illustrated in Fig. 2, constitutes a supply line 73, provided with a time fuse 7 4 which functions to open the circuit in case the motor draws more than the normal current. Y A relay for operating switch 76 for motor` 5 is con` trolled by a room circuit A which includes a pair of` thermostatic switches 77 and 78, designated as a room thermostat and a boiler thermostat, respectively, and conductors 77a, 77b and 77e. When these switches move to closed position due toa drop in temperature,

toya predetermined point, the circuit A is closed and is energized, closing the switch 76 and permitting current to flow through conductor 79 to a relay Winding 80 through normally closed switch 81, conductor 82 and thermal element 83,backto the line through conductors 84 and 85. 4 The starting current of motor 5 is heavier than the normal run'-y ning. currentf. thereof, and is sulicient to cause the relay to rock switch arm 86 around.its pivot 87against the action Uof spring 88. Thus a pin 86a on arm 86 momentarily moves away from spring contact member 89, permitting the member 89 to come in cont-act with .a Contact element 90.

The contact element 90 is connected by conductor 91 to a resistance element 92 which through a binding post 93 is connected to` the return conductor 84. This provides a shunt circuit for by-passing part of the starting current around the thermal element coil 4 83, through the resistance element 92. Thus an abnormal amount of current is prevented from flowing through the vthermal coil 83 which surrounds a bi-metallic thermostatic element 94 and prevents a too rapid heating of the element. The thermostatic element 94 is a safety feature which serves to open the motor circuit in case the normal required amount of heat is not developed after a predetermined. time upon the starting operation of the burner. In case proper heat is developed within such time, a stack thermostatic switch 52, Fig. 2, rocks to a position where the contacts 95 are connected by the mercury globule 96. Then part ofthe current nor-l mally flowing through the heating element 83 is shunted from 'conductor 79 through conductor 97, stack switch contacts 95 and back to the line through the conductors 98 and 85.

control box, is show-n vin Figs. 1 and 12, and y is preferably covered with insulating material.A Lever 81a carries a finger 81c in spaced and substantially parallel relation thereto and which is adapted to engage and bear down on the spring arm 99a ofarm 99 connection and keeps the contacts at 81 separated until the lever islowered to its normal position. Thus, if thermal element 94 isnot in its normal position to support the arm 99,- the circuit to the motor is not closed by` movement of the leverl81a.'

"when the lever- 81kw ieri-:miseri` to restoleilllg y,

lsof

of. 15 amperes for the pump motor passesk therethrough.

It. is desirable upon the starting operation of tlie burner, to create an artificial dra ft so that the normal operation of the burnermiay be insured at such time, and also prevent any possibility of back pressure in the furnace resulting in products .of combustion escaping 1n the wrong direction. For this purpose,

Vthe stack switch is normally in a position where the contacts 101 are closed by the niercury. Therefore, when switch 7G is closed, the stack fan is set in operation and continues to operate until the stack switch throws over to position to closed contacts 95. The return conductor 102 for the stack fan, leads back to the supply line in advance of the switch 76 and therefore, the operation ofthe stack fan does not effect the operation of thethermal element 83.

The circuit for the atomizer motor 3 is indicated on Fig. 2 by the numeral 103. These conductors connect the motor with the generator 4, the rotor of which is on shaft 41', and pass through the fuses 105, Fig. 2. The operation of the device is brought out in general in the foregoing description. One of the most characteristic features of this burner is in the application of the motor generator set to an oil burner in order to make possible the running of the induction motor for the atomizer at a higher speed than is possible on 60 cycles, for example, in the construction illustrated, the normal 60 cycles is stepped up to 180.

It is to be noted that the control system herein disclosed is particularly suitable for a motor in which the lstarting load is very high relative to its normal running load and this circumstance is a distinct advantage for me, instead of being a disadvantage.

Although but one illustrative embodiment' of this invention has been shown and described, many modifications may be had without departing from-the spirit of the invention, as defined in the following claims.

said generator, a rotative atomizing means directly connected to said vinduction motor,

thermal element, a thermostatic switch actuated by t-lie heat of the products of combustion for closing said stack circuit, and a circuit breaker in said stack circuit adapted to carry the normal running load of said pump motor and adapted to be opened by the starting load of said motor.

3. In a liquid fuel burner, a pump motor circuit, a room thermostat circuit, -means in said room circuit forl controlling saidv pump circuit, a safety switch in said motor circuit, a thermal element controlled by the current. in said motor circuit for normally holding said safety switch. in closed Vposition,'-a normally open shunt circuit comprising a resistance element for by-passing current around said electric thermal element, and means actuated by the starting load4 of said pump motor for closing said shunt circuit.

. 4. In a liquid fuel burner, the combination of a pump motor, a circuit including said motor, a fuel reservoir having a fuel outlet, a pump actuated by said motor for supplying fuel to said reservoir, an atomizer, means for supplying fuel from-said reservoir to said atomizer, a valve normally closing said fuel outlet, automatic means for opening said valve when said pump motorhas attained a predetermined speed, a safety switchnormally closing said circuit comprising automatic electrical means operable by the current in said circuit for actuating said switch to open said circuit, and 'manually operated means for by-passing the current around said safety switch, said 'manually operated means coacting with said fuel outlet valve for inhibiting the opening of the latter when the circuit is bypassed around said safety switch. v

5; In a liquid fuel burner, the combination of a pump motor, a pump operatively connected with said motor, a generator driven by said motor, a burner motor actuated by current from said generator, a rotative atomizing means directly connected with said burner motor, means for supplying fuel raised by said pump to said atomizing means, and thermostatic means for controlling operation of said pump motor.

Signed at Chicago this 21st day of Oct0ber,1926.

. HERBERT J. SAUVAGE.

Images