US2290893A - Apparatus for carbureting air for internal combustion engines - Google Patents

Description

July 28, 1942. E. E. PHILLIPS APPARATUS FOR CARBURETING AIR FOR INTERNAL COMBUSTION ENGINES 2 Sheets-Sheet 1 Filed May 31, 1958 II II II II II II III IL" II II II I] II II H II H INVENTOR jfmei y Jar/Lizzy;

'July 28,1942. E. E. PHILLIPS APPARATUS FOR CARBURETING AIR FOR INTERNAL COMBUSTION ENGINES Filed May 31, 1938 2 Sheets-Sheet 2 INVENTOR Patented July 28, 1942 APPARATUS FOR CARBURETING AIR FOR INTERNAL coMBUsrioN ENGINES Emer Phillips, Pittsburgh, Pa., assignor to Bocjl Corporation, trustee, Pittsburgh, Pa., a

corporation of Delaware Application May 31, 1938, Serial No. 211,090 5 Claims. (01. 261-21) This invention relates to the carburization of air for internal combustion engines. and is fora method and apparatus by means of which the air used in an internal combustion engine may be more effectively ca'rbureted 'to increase power: and eflic'ie'ncy. The invention is applicable to mobile internalcom-bustion engines such as those used on air planes, automobiles and tractors and boats, or may be used on stationary internal combustion engines.

In the operation of an internal combustion engine air is drawn, usually through a filter to the carburetor. It passes through the carburetor at a relatively high velocity. In passing through the carburetor at high velocity, the air sucks "is liquid gasoline from a jet in the carburetor and sweeps it with the air into the intake manifold where it is delivered to the internal combustion engines. The fuel is imperfectly vaporized and some of it is even carried along in a liquid phase to the cylinders of the internal combustion engine. I have discovered that, if instead of using a single carbureting device, the carburization is effected in stages, the engine will operate much more efiiciently on less fuel consumption and that the operation of the engine will be otherwise improved. This is particularly true where some of the fuel is supplied to the airthrough a capillary medium over or through which the air flows,

while the major portion of the fuel is supplied in g n the conventional manner to the air through 'ajet type of carburetor. All-of that fuel which is supplied to the air from the capillary medium enters the air exclusively as a vapor and not as a mist or spray. For some reason, which is not apparent to me, this gives a more effective method of carburization and produces economies and improved operating characteristics of the engine as above referred to.

I For example, with the present preferred embodiment of my invention, the air is preliminarily charged with a relatively slight amount of fuel before it flows into the carburetor. For some reason which I am unable to explain, this initial or incipient charging of the air with a small amount of fuel before passing it into the carburetor enables the use of a considerably less amount of fuel than that required by the same engine when there is only a single stage of carburization. Both block and road tests disclose that a considerably less amount of fuel is required for example by an automobile through the use of the present invention than with any of the standard methods of carburization. The increase in mileage per gallon of gasoline ranges about 50% or more. Not only is there a marked economy in fuel, but the engine runs more smoothly and has a quicker acceleration without knocking. Both block and road tests show an increased thermal efficiency and as a result of increased thermal efficiency, there is a reduction of oil consumption and a noticeable decrease in the accumulation of carbon. Incidentally, tests at the present time indicate that the increase in mileageis proportionately greater where so-called motor gasoline is used than where gasoline containing lead is used.

According to one form of my invention, the air filter lhay be provided with a capillary means through which the air passes and which 'is continually wet with fuel such as gasoline. A very slight amount of preliminary or incipient carburization is effected by the now of air through and over this capillary. The air, after passing through and-ever the capillary means is delivered to the carburetor of any usual or preferred construction where carburization is effected in the customary manner after which the fuel mixture passes to the intake of the internal combustion "engine and'is used in the usual way. The amount of :fuel evaporated from the capillary means is extremely-small, but for some reason this preliminary addition of "a very small amount of fuel to the air enables "the engine to run longer or further one. given quantity of fuel than Where such preliminary carburization is not effected.

Referring tothe d'rawings which illustrate certain embodiments of my invention,

Figure 1 is a transverse vertical section through a combined dust removing and preliminary carburetingunit embodying my invention;

Figure 2 is a :top plan view of the construction shown in Figure 1;

Figure 3 isa view similar to Figure 1 showing the upper portion only of a modified form of top for the 'u'nit illustrated-in Figure 1;

Figure '4 is a topplan view partly broken away of another former top for use on the unit shown in Figtire 1;

I Figure 5 is a transverse vertical section through "the topshowh in Figure 4 --Figure 6 is a more or less conventional view showing the assembly of an internal combustion engine, a carburetor, and the preliminary carbureting 'u n-it;

Referring iirst to Figure 6, 2 designates an internal combustion engine of any known or preferred cons'trucftion having an intake manifold 3 leading through -a heater 4 to a jet type carburetor 5. "In embodiment shown, the carburetoris of thedoWn-draft type with an air intake at the top. Onthe intake of the carburetor 5 is the auxiliary or preliminary carbureting unit 6.

' For-purposes of convenience, the preliminary or' auxiliary "c'arbureting device 6 may be constructediin the form of an attachment to replace the usualdust filter now generally provided on automobiles. 'I he'unit 8 may comprise an annular trough member l having a central chamber or well 8'ithere'in. Leading through the bottom of the structure is a tubular member 9 having a clamping collar by means of which the structure can be clamped to the top of the air intake pipe. At ii there is shown a dust filter comprising a mass of steel wool l2 confined between a perforated sheet 13 and a screen l3a. Across the top of the well or chamber 8 there is a wicksupporting structure, this structure preferably having a lower woven wire screen I4 and an upper woven wire screen [5, the two being as sembled as a unit. Extending across the lower screen l4 are a series of wicks l6 and extending across the upper screen l are similar wicks 11, one series of wicks preferably extending at right angels to the other. Both series of wicks extend down into the bottom of the trough 1 so as'to absorb fluid fuel which is supplied to the chamber 1.

Secured to the top of the trough member 1 is t a cover member l8 having an inner flange 19 which bears against the wicks. The member I8 with its flange l9 closes the bottom of the trough from the free circulation of air therethrough.

The trough member I is constructed with an outwardly turned flange 1a. Setting on the flange la is a removable dome 20. Supported in the dome 20 between wire screens 2| and 22 is a mass of steel wool or other air filtering material 23'. The top of the dome 2B is provided with a number of segment-shaped ports or openings 24 therein. Pivotally mounted on the top of the dome is a cover plate 25 having openings 26 therein which may be brought into and out of register with the openings 24 to control the supply of air that can enter the unit. The pivoted cover 25 may be lined on its under surface with a layer of felt 21 and it may be provided with a lug 28 connected to the choke-operating mechanism of the automobile or other engine.

In the use of the device, gasoline or other appropriate fuel is supplied to the trough I. This fuel is carried by capillary attraction into the wicks which become saturated throughout their length with the fuel. When the engine is not operating, th rotatable cover 26 should be turned so that the ports 24 are closed. By attaching the lug 28 to the pull rod of the choke-operating mechanism or similar device, this operation of the cover can be effected from the dash of the automobile or airplane or from any other convenient location. By closing the cover when the engine is standing idle, the free escape of fuel vapor is prevented. In starting the engine the movable cover 25 is ordinarily kept in a position to close the unit against the free inflow of air so that it is unnecessary to operate any butterfly valve in the carbureter for choking. When the engine is initially started, air within the unit is drawn through the carburetor and into the engine. Even though it is cold, it will be highly charged with fuel vapor and practically immediate starting will be had. As the engine picks up speed, the adjustable cover can be turned. to open the ports 24 wider and wider. The ports 24 and 26 are large enough to offer no obstruction to an adequate supply of air being drawn through the unit when the engine is operating normally or at high speeds.

When th air enters the unit, is is diffused and,

filtered in passing through the mass of material 23. It then flows through the screens which carry the two sets of wicks l6 and I! and in passing over the wicks evaporates a small amount of fuel. The air may be further filtered in passing through the mass of material l2 in the unit H, The unit II also is an effective check against back fire through the carburetor against the wicks. The air, upon having this preliminary or auxiliary carburization, then flows down the air intake pipe where it passes through the carburetor in the usual way. By reason of the preliminary vaporizing of the fuel in the unit 6, the air appears to more effectively vaporize or take up gas from the carburetor. It is possible in using the device to reduce the orifice in the main jet of the carburetor very considerably.

The rate of evaporation of fuel from the trough 1 is very gradual. In a range of commercial automobiles in which the device has been tested, fuel has evaporated from the trough I at an averge rate of around 1 quart per miles. The amount of gasoline consumed in the main carburetor, however, is very materially decreased because, including the fuel used in the unit 6, the average mileage in a number of cars has been increased from between 14 to 16 miles per gallon without the unit to 21 to 24 miles per gallon with the unit, and these results have been confirmed in dynamometer block tests.

The adjustable cover 25, while not essential to the successful operation of the device is quite desirable first, because it i unnecessary to use a conventional butterfly valve for a choke, and second, because when the car is standing idle, some evaporation will take place, and. if the unit were freely open to the air when the engine i not running, this vapor would be wasted.

The fuel may be supplied to the trough I from any suitable source. I have conventionally indicated a float valve 29 for controlling the flow of gasoline from a supply line into the unit. The same kind of fuel is supplied to the unit and to the carburetor, so that both devices may be coupled to the same supply tank and fuel pump.

In Figure 3 the general construction and ar rangement of the unit is similar to that described in connection with Figure 1 except that instead of having a manually controlled shutter or valve, a spring-closed and suction-operated valve arrangement is provided. In Figure 3, 28' desig nates the dome of the unit 6 similar to the member'Zll describedinconnection with Figure 1. The filtering material 3|] is confined between screens 3| and 32. The top of the dome 25 is provided with a central opening 33. Within this opening is a truncated cone-shaped member 34 having an internal spider 35. Between the screen 3i and spider 35 is a light compression spring 35. A flange 34 is provided on the base of the member 34 to limit its upward movement under the action of the spring. At the top of the member 34 is an opening 31, the member 34 having an inwardly turned flange 34a. Received within the opening 31 is another truncated cone member 38 having a bottom flange 38' which extends under the flange 34a and having a closed top 35a. A compression spring 39 isinterposedbetween the spider 35 and the top 3811. or member 38 so t'hatthe member 38 is urged upwardly by the action of the spring 39. It will be noted that in this form of device the upper filter 3D is spaced a little below the top of the dome. The construction and arrangement of the parts below the filter 35 and the wire 32 are the same for the device as corn structed in Figure 3 as described in connection with Figure 1. In operation, when the engine is started it withdraws air from under the dome 20 as described in connection with Figure 1. As the engine picks up speed, the member 38 will be drawn in by suction against the compression of 38 will be the first one to open.

In Figure 4 another modification employing spring-closed suction-opened valves is disclosed. In this figure 4 indicates the top of the dome member. It is provided with a plurality of openings 4| and 42. The openings 62 may be larger than the openings 4|. Under each of the openings there is a hinged flap or valve 33. thee valves being pivotally supported at 4. Leaf springs 25 tend to hold the valves closed while suction created within the device pulls the val es open. The strength of the springs 45 may he graduated in such a way that the ports 4! would open before the ports 32 and if desired they may be arranged to open in progression as the suction increases.

In the drawings I have shown certain specific embodiments of apparatu for the purpose of illustration, but it will be understood that the invention is not confined to the particular device shown. I prefer that the preliminary step of carburization shall be one effected through evaporation of fuel as this gives the desired initial diffusion of fuel through the air. The second step of carburization is preferably the conven tional jet type in which fuel is atomized because this type of carburization is most compact. Moreover, the evaporation step of preliminary carburization is intended to prepare the air for complete carburization in a standard jet type of carburetor to improve the function of the jet type of carburetor. The mixture of air and fuel produced by the preliminary step of evaporative carburization is of itself entirely too lean to satisfy the engine. The main carburetor may be adjusted to a point where it alone provides a mixture which is too lean to operate the engine. When the two units are used in combination, however, the mixture supplied to the engine is entirely adequate, although the total fuel con-- sumption in both units is less than that required Where only a single carburetor is employed. As previously stated, the reason why this is so is not apparent to me.

While the present preferred method and system of util zing my invention employs a capillary type of carburetor in advance of the conventional jet type, as specifically illustrated, advantageous results can also be secured by reversing the arrangement so that the air at first passes through the conventional type of carburetor and then through the capillary means.

I claim:

1. Carbureting means for use with an internal combustion engine having an intake manifold through which the air and fuel mixture is conducted to the engine comprising a succession of carbureting devices permanently connected and in fixed communication with each other and with he manifold and through which substantially all of the air for operating the engine passes to the intake manifold, one of said carbureting devices being a jet type of carburetor, the first of the devices in the path of flow of the air being of a type having capillary means of large area as compared to the area of the intake manifold to which fuel is supplied and the wetness of which is automatically regulated and against which the air flows whereby the air, in flowing to the manifold, first picks up a charge of dry vapor and thereafter is supplied with the main fuel charge.

2. For use with an internal combustion engine having an intake manifold, the invention which comprises in combination a jet type carburetor for supplying a combustible fuel mixture to the manifold, said carburetor having an air intake passage, and means over the air intake passage through which air going to the carburetor must pass comprising a capillary medium of large area as compared to the cross sectional area of the intake passage of the carburetor, a closed duct leading from said carburetor to the manifold, and means for supplying fuel to the capillary medium only by capillary attraction so that the supply of fuel on the capillary medium is automatically regulated, the air flowing to the carburetor being thereby caused to first evaporate fuel from said capillary medium.

3. For use with an internal combustion engine having an intake manifold, the invention comprising in combination a jet type carburetor for supplying a complete combustible mixture of air and fuel to the intake manifold connected with the manifold through a closed duct, said carburetor having an air intake passage, and means across the air intake passage through which air must pass to the carburetor comprising a curtain of absorbent material within an enclosure in permanent connection with the carburetor whereby it is operable at all times, and means for supplying fuel to the absorbent material whereby some of the fuel may be evaporated into the air before the air enters the carburetor, the supply of fuel to the absorbent material being regulated by capillary action, said intake manifold being substantially closed against air other than that which passes through the carburetor.

4. Charge-forming means for use with an internal combustion engine having an intake manifold, comprising in combination, a jet type carburetor for supplying a complete fuel and air mixture to the manifold, and a booster having a capillary means to which fuel is supplied and in which fuel is evaporated by air passing to the intake manifold, the carburetor and booster being in fixed relation, the former succeeding the latter so that under all conditions both the booster and carburetor act on the same air stream, the wetness of the capillary means being autogenously regulated.

5. A charge-forming device for internal combustion engines comprising capillary means forming a curtain through which air may flow, an enclosure for directing the flow of air through said curtain, the wetness of the curtain being autogenously regulated means for supplying fuel to the curtain, an air duct leading from the enclosure, a jet type carburetor having an air intake with which said duct is in permanent communication, the connection being such that substantially all of the air passing through the jet type carburetor is first drawn through said curtain.

EMERY E. PHILLIPS.

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