US2364132A

US2364132A - Oil burner

Info

Publication number: US2364132A
Authority: US
Publication date: 1944-12-05
Anticipated expiration: 1961-12-05

Description

Dec. 5, 1944. w. H. DE LANCEY 2,364,132

OIL BURNER Filed July 23, 1942 2 Sheets-Sheet l INVENTOR ATTo' NEYS 3 Dec. 5, 1944. w. H. DE LANCEY 2,364,132

OIL BURNER Filed July 23, 1942 2 Shets-Sheet 2 ATTO NEYS Patented Dec. 5, 1944 tlon of Massachusetts Application July 23,1942, Serial No. 452,019

4 Claims.

This invention relates to improvements in oil.

burners and, more particularly, to improvements in the ignition means thereof.

The invention has for one object to provide in an oil burner. an ignition supply from a separate generator, such as a magneto, driven from the burner motor and directly supplying the ig: nition electrodes, as distinguished from a transformer or other means which is electrically connected to the electric service wires supplyingother household devices and appliances. The

on. BURNER Warren H. De Lancey, SpringfielrL Masa; as 1 signor to Gilbert & Barker Manufacturing Company, West Springfield, Mass.,-a corpora- V nozzle of the burner. hetween'the con-i. duits I and I6 is a pressureiregulating and by-: pass valve, indicated conventionally at 1|.." This arrangement is characterized in that potential radio interference from the fluttering of the spark is confined to the separate and independent ignition circuit and cannot be fed back into the,

aforesaid service line. The invention has for another object the provision in a burner having an ignition magneto, driven from the burner motor, as well as an oil pump also driven from such motor, of means responsive'to the speed of the magneto iorcoupling and uncoupling the pump. to themotorwhenever the magneto respectively reaches or falls below a predetermined speed.

These objects will best be understood as the detailed description proceeds and they will be pointed out in the appended claims.

The invention will be disclosed with reference to the illustrative embodiment of it in the accompanying drawings, in which:

Fig. I is a small-scale side-elevational view of the oil burner;

Fig. 2 is a sectional plan view of the air-supply conduit showing the oil nozzle and ignition electrodes; a

Fig. 3 is a sectional elevational view of the motor-driven air-fan, oil-pump andignition generator;

Fig. 4 is across sectional view taken on the line 44 of Fig. 3; and

Fig. 5 is a diagram showing the motor circuit in part and the complete ignition circuit.

Referring to these drawings; the burner chosen for illustrative purposes is of the so-called gun type. It includes, as schematically shown in Fig. 1, an electric motor H) which drives an oil pump II and a fan, located within the casing I2. Connected to and projecting from the lower part of the casing I2 is an air-supply conduit I3 having its axis parallel to ,that of the motor III. This conduit l3 contains the oil nozzle, ignition electrodes and any other related parts that are necessary or usual in a burner of this kind. Oil is supplied to pump H by a conduit I4 and forced by the latter through conduits I5 and It to the.

} under high pressure by pump emitted in; the'form of a hollow. conical spray and"in exceedin'gly finely dividediorm like amist oriog valve has a'by-pass conduit I8 extendinghack'w the suction side of the pump'or to the oi oil supply. This valve prevents oil fromjpassing to the nozzle until it has been placed under a.

predetermined pressure, say for'exam ple 125 p sr quare inch. "The valve also by-" passes some of the pumped'oirback to the supply by way of conduitJ8, whenever-the oil is in excess of the requirement of .the burner...

Referring to Fig. 2, the oil nozzle is shown at I9. This nozzle is of the so-called mechanical or pressure-atomizing type. Oil, forcedthrough it Air supplied by the fan is iorcediunder relatively low, pressure through conduit I3 to mix with the oil spray. The part marked 20 is an air director.

of any suitable form. Spark electrodes .2l ;'are

positioned adjacent .the oil sprayto ignite the same. Incidental1y, these electrodes lie in the pathof the air. These electrodes aremounted.

" one in each of'two insulators 22 and their'fouter.

disclosureif such is necessary or. dQSi16dr-;

ends are connected .by' Wires 23"to the sourceof ignition current. These wires may, as indicated in Fig. 2, pass out of conduit l3 through a. re-,

movable end closure 24 and into and through. a

shielding conduit 25 which as indicated in Fig. 1 extends to the casing of motor H1. Thenozzle I9 is mounted on a tubular nozzle support26 to the outer end of which oil feed conduit l6 isconnected. -The general arrangement and the mounting of the parts in conduit I3 is substan tially like that disclosed inthe I'Ifapp et al. U. S.

Patent No. 2,227,286, dated December 31, 1940.

to which reference is made for a more complete disclosure. r v

The mounting of theian housing l2 and the connected conduit l 3 together with-the mounting of-the motor I0 is or maybe as shown in my US. Patent No. 2,262,52 granted Nov. 11, 194 1, to

which reference is madefor a. more complete Referring now toEig. 3, the motor 10 includes a casing 21 one nd of.which liesadjacent the I fan housing I 2 and in line with an opening therein which lies oppositethe airinlet 28 of the housing. ventionally at'29 and 30, respectively. The rotor shaft is shown at 3| with its-inner (left hand) end fixed to the rotor. The fan 32 is fixed to The stator and rotor are indicated con to 'the coil 31.

Also, by its location in compartment;

3| and a stator comprising side laminations 35 and a. connecting core 36, carrying aeoil. 31. Th magneto may, for example, be. constructed as shown in U. S. patent to Harmon et al., No.

2,043,042, dated June 2, 1936, except for the omission of the breaker mechanism and distributor and the use of a single coil in place of the two there shown. The side laminations 35 may be cast into; a frame '33 and the latter secured, as indicated, to the motor. casing. The ignition wires ,23 preferably enter compartment 33 through the shielding conduit 25 for connection The electrical connections are shown diagrammatically in Fig. 5. The ignition circuit is entirely independent of the circuit in which motor i is located, as will be clear from Fig. 5. Also, as willbe clear from the preceding description, the ignition circuit is completely shielded from the motor circuit and the motor.

The motor i0 also drives the oil pump I I. This pump maybe of any suitable form. As shown, it comprises an internal gear 39 and a spur gear 40 which intermesh and are mounted between a pair of end walls 4| and 42, heldapart by. a spacer 43. The gear 40 is fixed to a shaft 44 y ca'ted coaxially of motor shaft 3| and driven therefrom in-a'special manner as will later ap- 7 pear. The gear 39 is free to rotate within the casing formed by walls, 42 and 43. Wall 4| has formed therein inlet and outlet ports 45 and 46, respectively, for the pump, which ports are respectively connected by conduits 41 and 48 to theinlet conduit and outlet conduitl5 above described. This type of pump is more fully disclosed in my U. S. Patent No. 2,230,717, dated Feb. 4, 1941', to which reference is made for a. more complete disclosure if such is necessary or desired. The oil pump is so driven in relation to the magneto that the latter is enabled to be broughtup to full speed by the motor Ill before the oil {pump is started. This insures that adequate ignition voltage is available to produce ignition sparks between'the electrodes before any oil'can possibly be emitted from the nozzle [9. This result may be secured by any suitable speed-responsive means which couples the pump shaft 44 to the magneto driving shaft 3| only after the latter has acquired a sufficient predetermined speed. As an example of one means suitable for the purpose there is shown in Figs. 3 and 4, a centrifugal clutch. This clutch has a, hollow cylindrical casing 49 fixed to pump shaft 44 and a disk 50 fixed to shaft 3| and located so as to substantially close the open face of the casing 49. The disk 50: car

ries two weights 5|, pivoted one to each of a pair of studs fixed to the disk. Springs 53 tend to draw the weights radially inwardand to hold them in their innermost positions shown in Fig; 4.

Each weight preferably carries a frictionband 54 adapted to engage the inner peripheral wall of casing 49 when the weights 5| are thrown outnecessary speed, grip the casing 49 and thereby rotate it and with it the oil pump.

It is to be noted that the fan 28 is also enabled to build up speed before the oil pump is started. This has the important advantages set forth in U. ,S. patent to Logan No. 1,985,934, dated January 1,.1935. It is desiredtoretain all these advantages and to secure additional advantages which cannot be secured from the Logan structure and which relates entirely to the ignition system of the burner.

The ignition system shown is of the simplest form as will be clear from Fig. 5. It includes simply the magneto generator, the spark electrodes and connecting wires. This system affords .so-called continuous ignitionthat is, the ignition is operating whenever the burner motor is operating. One trouble that developed in prior burners of this general type was radio interference of a peculiar'type. This interference resulted from fluttering of the ignition spark caused by the air current in the path of which the electrodes are located. The fluttering of the spark caused a high frequency disturbance. which was fed back into the electric power line because, in

accordance with prior practice, the ignition was supplied by a transformer connected to said line. The nearby radio sets connected to the same line suffered from the arrangement. Also, the disturbance was not merely momentary but was prolonged because the ignition remained on as long as the burner was operating. Shielding did not; cure this sort of radio interference and it was necessary to use-a so-called radio filter for the purpose.

With the present system, the radio filter and theignition transformer are dispensed with and inv their place a magneto of simple form is provided. A saving in cost is efiected because the magneto is less expensive than the transformer and filter combined. And a saving in space is effected because the magneto can be housed within the motor casing. It is to be noted that this magneto is shielded from the motor and that the wires of the ignition circuit are shielded by conduit 25 and air conduit l3. Consequently, any high frequency disturbance that may be created can be fed back only into the ignition circuit which is entirely separate and independent from the power circuit which supplies the burner motor, radio sets and other electrical devices and appliances. Such disturbances are confined to the ignition circuit and, since the latter is fully shielded, the disturbances cannot be inductively picked up by adjacent wires of the power circuit.

The conventional transformer ignition system, commonly used heretofore for burners of the present type, is instantly available to supply ignition sparks whenever the burner is started. That is, the transformer can be brought into full action coincidentally with the burner motor by simply closing a single switch. With the mag- I. netoignition, which is important and desirable as wardly by sufficient centrifugal force. Thus, these weights, which rotate synchronously with the magneto will, after thelatter has acquired the above set forth, there is a slight delay before full ignition voltage is available. Therefore, it becomes necessary to so relate the magneto to the pump as to insure that the magneto will be brought up to speed befor oil is emitted from the nozzle. v

The invention is particularly satisfactory for burnersof the so-called pressure-atomizing type but it is not necessarily limited thereto in all its features. The pressure-atomizing nozzle requires the building up of very high oil pressure and this imposes a heavy load on the driving motor, materially retarding the fan and magneto from building up proper speed. The speed-responsive device enables both fan and magneto to be much more quickly brought to proper speed and the oil pressure is built up afterward and after adequate air and ignition are available for the very first oil emitted from the nozzle. So, too, on stopping of the motor the oil-pump is uncoupled before the magneto and fan stop. As soon as the pump is uncoupled, it stops quickly thereby stopping the flow of oil from the nozzle. But the fan and magneto continue in action for a while due to the momentum of the heavy rotor of the motor and long enough to insure ignition for the last drops of oil which pass the nozzle.

What I claim is:

1. In an oil burner, a nozzle for emitting the oil, means controlling the flow of oil to the nozzle, a conduit for conducting air to the nozzle to mix with the oil, spark electrodes positioned to ignite the oil spray, means for causing a flow of air through said conduit, a magneto, an electrical circuit including the magneto and electrodes, a motor for driving said magneto, and means coordinating the operation of the magneto and oil-flow controlling means to enable flow of oil to said nozzle only when the magneto is moving at sufficient speed to provide ignition sparks at said electrodes.

2. In an oil burner, a pressure-atomizing nozzle, a pump for supplying oil thereto'under high pressure, a conduit connecting the pump and nozzle, a pressure-responsive valve interposed in said conduit and opening to allow flow of oil to the nozzle only after the pump has built up the l speed which is high enough to generate suflicient voltage and insure a proper ignition spark between said electrodes and operable on deenergization of said motor or on a drop in speed thereof below said predetermined speed to uncouple the pump from the motor and stop the flow of oil from said nozzle. n

3. In an oil burner, a pressure-atomizirng nozzle, a pump for supplying oil thereto under high pressure, a conduit connecting the pump and nozzle, a pressure-responsive valve interposed in saidconduit and opening to allow flow of oil to the nozzle only after the pump has built up the requisite high pressure, a conduit for conducting air to the nozzle to mix With the atomized oil, a fan for forcing air at relatively low pressure through said conduit, spark electrodes in the air conduit positioned to ignite the oil spray from said nozzle and positioned also in the path of the air flow, a magneto connected in circuit with said electrodes; an electric motor in a circuit unrelated to the first-named circuit for driving the pump, fan and magneto; means connecting the magneto to the motor to stop and start coincidentally therewith, and means responsive to the speed of the magneto operable to couple the pump to the motor only after the magneto has acquired a predetermined speed which is high enough to generate sufficient voltage to insure a proper ignition spark between said electrodes and operable on deenergization of said motor or a drop in speed thereof below said predetermined speed to uncouple the pump from the motor and stop the flow of oil from said nozzle.

4. An electrically-operated fuel-supply and ignition unit for oil burners, comprising, an electric motor having a stationary housing and a revoluble driving shaft, a high tension ignition generator mounted within said housing and directly coupled to said shaft, a fuel pump mounted on said housing and having a driving shaft, and a single means for coupling said shafts operable automatically in response to centrifugal force to couple the shafts and drive the fuel pump when and only when the motor shaft and thus said generator exceeds a predetermined speed to insure an adequate ignition supply before delivery of fuel by the pump.

WARREN H. DE LANCEY.