US2016771A - Carburetor - Google Patents

Description

Oct. 8, 1935. s. EISSING 2,016,771

CARBURETOR Filed July 15, 1933 2 Sheets-Sheet l 17 INVENTOR 22 ATTORNEY.

Patented Oct. 8, 1935 UNITED STATES CARBURETOR.

Gustav Eissing', Secaucus, N. .1.

Application July 15,1933, Serial No. 680,562

11 Claims. (Cl. 261 -41) My invention relates to improvements in carburetors for internal combustion engines and has reference particularly to a device of this character embodying in its construction a plurality of vaporizing tubes disposed in the mixing chamber 7 and separate high and low speed chambers individually controlled for feeding automatically the proper amounts of fuel to the mixing chamber for difierent engine speeds. The invention has for its object to provide a carburetor of the above stated character which will be highly efficient in its fuel consumption, relatively easy to regulate and extremely durable In use. I accomplish this object by means of the present invention of which one embodiment is described in the following specification, set forth in the appended claims and illustratively exemplified in the accompanying drawings, in which, Figure 1 is a perspective view of the assembled carburetor; Figure 2 is a substantially longitudinal sectional view of the same; Figure 3 is a side elevational view of the invention showing certain parts in section; Figure 4 is a substantially transverse sectional view of the high and low speed valves taken on lines 4-4 of Figure 5; .Figure 5 is a top plan view of the body on lower section of the carburetor showing the vaporizing tubes and interior of the float chamber; Figure 6 is a per- 3 spective view of thefixture embodying the vaporizing tubes; Figure 7 is a substantially transverse sectional view of the float chamber housing and valve taken on lines 'I-'I of Figure 3.

Referring to the drawings; I0 denotes the lower 35 shell or body portion of the carburetor and II the housing, which constitutes the mixing chamber, and which is mounted directly upon the shell Ill. The shell I0 is an integral casting and comprises the air intake chamber I2 and fuel or float 40 chamber I3.

The float chamber I3 is an upright cylindrical container having a relatively small upright cylindrical valve chamber I4 disposed in its, wall and in communication with the float chamber I3 45 through a narrow passage I5. The lower end of the valve chamber I4 opens into a lateral cylindrical chamber I6, which is closed at one end by a threaded plug I1, and which is provided at its other end with an intake plug I8 carrying an 60 angle fitting I9 and union 20 for the end of the fuel line. A suitable clean out plug 2I is provided in the under mid portion of the chamber I6 and carried axially of the latter upon the projecting inner ends of the plugs I! and I8 is a cylindrical screen 22, whereby fuel admitted through the intake plug I8 passes through the screen 22 before entering the chamber, as illustrative'ly exemplified in Figures 2 and 4. The valve chamber I4 and screen chamber I6 areseparated from eachother by a wall 23, which is '5" part of the casting, and which is provided with a threaded opening 24, alined with the clean out opening having the plug 2|, to accommodate a removable valve seat 25. The seat 25 comprises a cylindricalsection having one end threaded to 10 screw into the opening 24 and an enlarged mid section 26 to seat against a washer 21 on the bottom wall of the valve chamber. The upper free end of the seat 25 is provided with lateral slots 28 disposed just above the mid section 26, the 15 slots 28 establishing communication between the passage in the seat 25 and the valve chamber. Loosely arranged in the upper end of the seat 25 is a needle or float valve 29 having its tapered and pointed end projecting into the seat 25 just 20 below the slots 28, as illustrated in Figures 2 and 7. The upper end of the valve 29 has a reduced neck and head portion 30, the neck being embraced by a yoke 3| of a lever 32, which is pivoted on a pin 33 projecting between the walls 25 of the passage I5, and which projects into the float chamber I3 and carries at its end a float 34. The float and valve chambers are closed by a cover plate 35 which is held down by a plurality of screws 36 disposed marginally thereabout and screwed into threaded openings in the walls of the chambers. In accordance with this construction a constant fuel level is maintained in the float or fuel chamber I3, because any tendency of the fuel level to lower will cause the float 34 to drop and the valve 29 to open, admitting fuel from the strainer chamber I6 to find its way past the valve and slots 28 into the valve chamber and thence to the fuel chamber I3.

The inside wall of the fuel chamber I3 is pro- 40 vided with two bores or passages 31 and 38, the former leading to an upright high speed needle valve chamber 39 arranged on one side of a line drawn between the vertical axes of the air and fuel chambers, the other passage 38 being disposed to provide an opening into a second upright low speed needle valve chamber 49 on the opposite side of said line. The chambers 39 and 40 are each threaded at their opposite ends, the lower ends thereof being closed by plugs 4| and 50 restricted in the spaces above the latter by valve chambers 39 and III is controlled in its passage of which is adjustably mounted in a clamp nut 45 disposed in the upper threaded 'end of the chamber, as illustratively exemplified in Figure 4, so that when the valves have been adjusted satisfactorily, their positions or adjustments are made permanent by turning down on the clamping nuts 45.

At low speed the fuel being admitted into the low speed chamber 40 passes into a chamber 46,

disposed intermediate the high and low speed chambers, through a passage 41. The chamber 46 consists of an enlarged bore at its lower end which is closed by a plug 48. The upper portion of the chamber or bore is of smaller diameter and at its opposite ends it is threaded, the lower end accommodating a spray nozzle 49. The upper end of the smaller bore is provided with an upright tube 59, which screws into the threads and projects downwardly to a point just short of the tip of the spray nozzle 49, and which has a bore tapering to a smaller opening directly over and in register with the tip of the nozzle, the portion of the end of the latter surrounding the tip being a circular channel 5| to conform to the adjacent rounded off end of the tube 50.

The upper end of the tube is a. nut 52 provided with a slightly tapered seat 53 and bore opening into the main bore. ,Telescoping into the latter bore is a second tube 54' provided with external threads at its mid section to accommodate a nut 55 adapted to be adjusted over the threads to bring its tapered under surface into intimate contact with the tapered seat 59 of the tube 59. The second tube 54 is provided with a nut portion 56 short of its upper end which is threaded and screws into a threaded opening of an L-shaped projection 51, the longer arm of the latter being integral at its inner end with the shell of the mixing chamber and having its bore 58 opening into the latter through a reduced portion 59, as illustratively exemplified in Figure 2. Air is admitted to the upper portion of the chamber 46 through an opening 60 and adjustable valve 6| screwed into the opening and arranged on the outside of the casting.

Fuel entering the high speed chamber 89 follows a branch passage or bore 62 in a lateral projecting pipe-like portion of the casting between the float chamber shell and the lower shell, the passage 62 opening into a lateral bore 63 in a bridge piece 64'cast in the interior of the air chamber l2 and disposed between the wall thereof at one end and an upright tube-like center column65, the bore of which constitutes the high speed fuel chamber 66. The chamber 66 opens out of the bottom of the casting l6 and is closed by a clean out plug 61. I'he upper portion of the column 65 above the bridge piece 64 is increased in diameter and provided with a lateral branch pipe-like projection 68 integral at its outer end with the wall of the casting Ill. The bore 69 of the branch 68 is open to atmosphere at its outer.

end and to the chamber 66 of the column 65 at its inner end, thus establishing a primary air passage. Disposed within the enlarged portion of the column 65 is a spray nozzle 10, which is threaded at its lower portion and screwed into the upper end of the fuel passage or chamber 66. It is important to note that the tip of the nozzle 19 is disposed at a level whichis just above that of the fuel level indicated by the dotted line L in Figure 2, so that the fuel itself will be maintained within the nozzle and just below the tip thereof ready to be drawn out by the passage past the seats 42 by needle valves 43 and 44, each .01 air over the tip and into the mixing chamber.

The upper end of the enlarged portion of the column 65 projects above the branch 68 and is interiorly threaded to receive a threaded nipple of a cone tube H which consists of a nut mid 5 portion, an exteriorly threaded upper nipple, and a tapered bore 12 having its smaller end directly over and'spaeed slightly from the tip of the spray nozzle 10. The spray of fuel and air being drawn out of the cone or tapered bore 12 10 follows the surface of a slightly concave disc .plate 13, which has a central threaded opening to .screw down on the upper threaded nipple of the the least resistance possible to the flow of air from the air intake chamber l2 into the mixing chamber ll.

In the present embodiment of the invention I 25 have shown four openings 15 and a peripheral shoulder Hi. Just inside the shoulder 16 on diametrically opposite points of the upper face of the disc 13 are openings to accommodate pins 11, one thereof being fixed in the disc and the other 30 being carried by the annular base portion 18 of a plurality "of vaporizing tubes I9. The under surface of the base at its edges is provided with a depending ridge adapted to seat in and against the shoulder 16 ,of the disc 13. The side of the 35 base 19 fits snugly in the lower open end of the mixing chamber l I and the tubes 19 comprise four from the air chamber to make its way into the vaporizing tubes, which at their lower ends are rounded oif and spaced from the openings'15 to offer the least amount of resistance possible to the movementof the air. Each tube 19 has a 5 conical bore 80, the smaller end being at the bottom and adjacent the opening 15 and theupper end having the walls rounded off, as illustrated particularly in Figure 2. J

The upper portion of the mixing chamber ll 5 is virtually a neck to accommodate the throttle valve 8|,which consists of a disc turning with a shaft 82 disposed diametrically of the neck and journaled in bearings 83 cast integral with the shell I l. Control arms 84 are fixed on the 55 shaft 82 at one end thereof to receive the usual connections for operation of the valve. In closed position of the valve 8| the disc is slightly inclined downwardly towards and below the opening 59, so that at low speeds, fuel and air drawn up 50 through the chamber 46, may pass directly to the intake manifold over the valve. Connection with the intake manifold of an engine (not shown) is made by means of a flange 85 integral with the upper end of the neck portion of the mixing chamber.

Referring now to the air intake chamber l2, the latter is provided with a flange 86, which abuts a flange 81 of a tube 88, the tube having a choke 89 adjacent its inner end. The choke com- 70 prises a disc mounted on a shaft 90 which projects transversely of the tube and carries at one end the usual control connecting arm 9 I. Beyond the choke the tube 88 is provided with an annular depression 92 and side openings or slots '93. An

Theoperation of the carburetor according to the present invention is substantially as follows: Fuel from the fuel supply tankenters the carburetor through the angular fitting l9 and screen 22 and thence past the valve 29- into the float chamber I3, whereby a constant level is maintained by means of the float 34. Fuel then enters the high and low speed passages 39 and 40, respectively, where it is controlled by the separate needle valves 43 and 44, which when properly adjusted are locked by tightening the clamp nuts 45. To start the engine, the choke 89 is set to nearly closed position and thereby causes'a heavy movement of air through the primary air opening or passage 69. This movement of air causes fuel to be drawn out of the tip of the spray nozzle 10, through the cone tube II and into the space between the disc 13 and base 18 of the vaporizing tubes 19, where the air and fuel are distributed between the tubes as they pass over the rounded ends of the latter and are drawn through the conical bores 80 into the mixing chamber ll.

When the engine actually starts, the choke 89 opens and air is brought into the air chamber I2 through the secondary air inlet tube 88 and into the mixing chamber ll through the openings 15 in the disc 13 and conical bores 80 of the vaporizing tubes. As the air traverses the spaces between the openings 15 and the adjacent ends of the vaporizing tubes themixture of air and gas from the nozzle 10 and cone H is drawn into the conical bores 89 and thence to the mixing chamber I I.

At low speeds the throttle 8| is adjusted to nearly its closed position and fuel and air are drawn upwardly through the telescopic tubes and 54 and finally to the neck of the mixing chamber H by way of the bore 58 and restricted passage 59 and at a point slightly above the throttle 8|. speed chamber 46 through the valve 6 I and is then drawn down over the spray nozzle 49 which is disposed below the fuel level, whereby a finely divided spray is picked up by the air passing upwardly through the tube 59, the latter being adjusted to regulate the air intake.

Having now described my invention and the manner in which the same operates, what I claim and desire to secure by Letters Patent is:

1. In a carburetor, the combination of a nozzle disposed in an air inlet passage for supplying air and fuel to a mixing chamber, a tapered passage leading upwardly from the nozzle and a plurality of vaporizing tubes spaced above the nozzle and disposed in communication with a second air intake passage and arranged in said mixing chamber over the tapered passage to receive a mixture of air and fuel from said nozzle and to direct it into the path of air being drawn through the said tubes from the second passage to further vaporize said mixture reaching the mixing chamber.

2. In a carburetor, the combination of a nozzle disposed in an air inlet passage for supplying air and fuel to a .mixing chamber, a tapered pas- Air is admitted to the upper end of the low aperforated conical bottom wall for the mixing chamber to admit air into the latter, and a plurality of tubes disposed over and spaced from the perforations in said wall whereby air and fuel from said nozzle are introduced through the pas: 5

sage between the bottom wall and tubes into the paths of air being drawn through the perforations and tubes into the mixing chamber.

3. In a carburetor, the combination of a mixing chamber for air and fuel, a nozzle disposed 10 in an air passage to supply fuel and air to said chamber, and a vaporizing unit spaced above the I nozzle and disposed in the mixing chamber, comprising a conical base having a plurality of openings to admit a secondary draft of air into the 15 chamber and a passage registering with the nozzle to conduct fuel and a primary draft of air in a space above said base, and a plurality of vaporizing tubes registering with the openings in the base and projecting into the mixing cham- 20 ber, the ends of the tubes adjacent the base being spaced therefrom and in communication with the space receiving fuel and air from the nozzle, whereby the said fuel and air are drawn into the path of air constituting the secondary draft.

4. A vaporizing unit for a carburetor, as claimed in claim 3, in which the said tubes have conical bores, the axes of which converge to a point overhead.

5. A vaporizing unit for a carburetor, as 90 claimed in claim 3, in which the said tubes are embraced at their lower ends in an annular base, said tubes having conical bores, the smaller ends thereof opening below the base and having their axes converge to a point overhead on the center axis of the base.

6. A vaporizing unit for a carburetor, as claimed in claim 3, in which the said tubes are integral with an annular basesupported on the first base, the axes of the tubes converging to a 40 point overhead on the center axis of the base, said tubes further having conical bores with the smaller ends open below the base, the latter on its under side being provided with a chamber constituting the space above the first base and 45 opening into the tubes between the lower ends of the latter and the openings in the first base.

' 7. A vaporizing unit for the mixing chamber of a carburetor, comprising a plate forming the bottom of the mixing chamber and having a p1u- 50 rality of openings with their walls rounded off from the under side towards the top, and a plurality of tubes registering with the openings and spaced therefrom to form a space to admit fuel into the tubes between the latter and the plate, 85 the tubes having conical bores with their wider openings at their upper ends and their axes converging to a point overhead on the center axis of the unit, the lower ends of the tubes being rounded off on both sides and the upper ends being rounded off on their inner sides.

8. A vaporizing unit, as claimed in claim I, in which the tubes are supported in a skirted base having a chamber disposed on its under side to receive and distribute sprayed fuel over the lower ends of the tubes and into paths of air passing upwardly therethrough. c

9. In a carburetor, the combination of a nozzle disposed in an air inlet passage for supplying air and fuel to a mixing chamber and means for 70 maintaining a constant head and supply of fuel in and below the discharge tip for the nozzle, separate high and low speed fuel valve chambers, each provided with passages into the fuel supply means and valve seats having adjustableneedle' valves therefor, thechamber for high speed being interposed between the means for maintaining the supply of fuel and the nozzle, the valve chaming nozzle, a primary air inlet to supply air to the tip of the first nozzle, and vaporizing means spaced above the first nozzle and disposed in said mixing chamber to receive a mixture of air and fuel from said first nozzle and direct it into the path of additional air being drawn through said vaporizing means.

10. A carburetor, comprising a casting provided with a primary and a secondary air intake, a choke in the secondary intake, a high speed fuel chamber disposed upright in the casting and opening into the primary air intake, a spray nozzle arranged in the fuel chamber between the latter and the primary air intake, a cone unit spaced above the nozzle to conduct the air passing over the latter and the fuel therefrom in an upward direction, a disc mounted on the cone unit for closing the top of the secondary air intake and provided with a plurality of openings, a

ment in the mixing chamber comprising a plurality of tubes registering with and spaced above the openings in the disc and a chamber to receive 5 and distribute the mixture of air and fuel from the cone unit into the path of air being drawn from the secondary air intake, a throttle arranged in the upper end of said mixing chamber, high and low speed fuel chambers, the former 10 being connected to the high speed fuel chamber, a low speed fuel chamber in communication with the low speed valve chamber, a nozzle spraying fuel in the low speed chamber and an air inlet to supply air over the second nozzle, a separable 15 connection between the low speed fuel chamber and the mixing chamber above thethrottle therein, and means maintaining a constant head and supply of 'fuel for both nozzles, the level of the head of fuel being above the elevation oil the secgo 0nd nozzle.

11.iA carburetor, as claimed in claim 10,'in which said separable connection comprises a depending tube carried by the mixing chamber casting, and an upright tube projecting from a point 25 at its lower end over the second nozzle to telescopically embrace the lower end of the first tube.

GUSTAV EIssmG.

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