US1296363A - Fuel-feeding device for internal-combustion engines. - Google Patents

Description

c. 's. BURTON. CE FOR INTERNAL COMBUSTION ENGINES. v

Patented M314Z1919.

FUEL FEEDING DEVI APPLICATION FILED IULYY 9.1911. 1,296,363.

M671, 7' (arda ci ar/02a ill CHARLES S. BUR-TON, 6F OAK PARK, ILLINOIS.

FUELFEEDING DEVICE FOR INTERNAL-COMBUfiTIONENG Specification of Letters Patent.

Patented Man. a, rate.

.lkpplication filed July 9, 1917. Serial No. 178,579.

To @125 whom it may concern:

Be it known that I, CHAiiLns S. BURTON, a citizen of the Uni-ted States, residingat Oak Park, iiuthe county of Cook and State of Illinois, have invented new and useful Improvements in Fuel-Feeding Devices for Internal-CombustionEngines, of which the following is a specification, reference being had to the accompanying drawings, forming apart thereof.

The purpose of this invention is to pro vide an improved structure of the character commonly called a vacuum feed device, for

supplying liquid fuel to an internal combustion engine. It consists in the elements and features of Construction shown and dc.- scriloed as indicated in the claims.

In the drawings Figure 1 shows aside elevation of a portion of an engine equipped with this invention, he portion of the engine illustrated comprising theananifold and intake tube.

Fig. 2 is am an axial section of the air intake tube and of the liquid fuel supply device connected with the float chamber which is shown in elevation.

Fig. 3 is a section at the line, 33, on Fin. 2.

big. 4 is a plan view of the slitted flange at the line, 4-4, on Fig. 2.

In the drawings 1 represents the intake manifold, 2, the intake leading thereto, 3 the Venturi tube forming a portion of the air intake, 4, the customary float chamber or level-controlling chamber with the fuel nozzle leading from the float chamber and discharging within the Venturi tube; 5 is a main low level fuel supply tank from which a tube, 6, leads to a chamber, 7 in which a vacuous condition is to be produced for causing the liquid fuel to be lifted from the low level tank, 5. 8 is a supplemental reservoir into which the chamber, 7, discharges, and from which the liquid fuel is supplied by gravity to the float chamber. 4. of the ca-rbureter. 9 isa tube leading from the top of the chamber, 7, into and opening within the Venturi tube. 3, within the low pressure or high suction area of said Vcnturi tube which is indicated-by dottedflines at Said tube, 9, opens in the chamber, 7, through a restricted port. 9, which is designed to be continuously open, being unprovided with valve or the like for closing it. The chamber, 7, has an atmosphere port,

10, which is large relatively to the restricted her is filled with the first port, 9, and which is controlled by a valve, 11, carried at the upper end of a stem, 12, which is guided at its lower end by a spider or the like, 13, over the port, 14, by which the chamber, 7, dischar es into the chamber, 8, the discharge being free notwithstanding said stem which obstructs the passage to a negligible extent. is a valve 0 which the liquid is discharged by avity rom the chamber, 7, into the chain er, 8. 18 is a float mounted for sliding on the valve stem, 12, between two sto s, 16 and 16 thereon. The mouth of the air inlet port, 10, is controlled at its upper end by a woven wire or perforated metal screen, secured by a fianged nut, 19, the screen serving to limit the opening movement of the valve. The boss, 17,

through which the air inlet port, 10, is

formed, is provided with a depending flange or skirt, 20, whose lower edge is serrated or furnished with a multiplicity of slits, 20.

21 is an annular upwardly-open pan or cup forming a trap chamber supported from the ca pl te, 8", of the two chambers, 7' and. 8,

(t e c iamber, 7, being formed depending into the chamber, 8) said annular pan or tra chamber being of such depth and so positioned that the lower serrated or slitted edge of the flange, 20, depends into said pan around the inner circumferential flange wall thereof. Said annular pan or trap chamber extends under the intake or dis char e mouth of the tube, 6, which delivers the liquid from the low level tank into said chamber, 7, whereby said an or trap chamdischarge of liquid into said chamber and is rc-filled at the commencement of each fiiling action of the device when it has to any extent been drained or partly emptied during the discharge of the contentso'f the chamber, 7, into the chamber. 8.

The capacity of the device described for serving its purpose of lifting the li uid fuel from a low level tank to a supp emental reservoir at .a higher level from which it may be supplied to the engine by gravity, is due to the location of the mouth of the suction tube within the low pressure or high suction area of the Venturi tube, 3. It is known that an air current flowing through a tube of the character commonly called a Venturi tube such as shown in the drawings'tends to produce an area of reduced pressure at a short distance inward from the throat or most restricted point of the tube, said area of reduced. pressure being,

that the degree of vacuum existing in this low pressure space or arc'aincreases with t e rate of flow of the air through the tube. so that a very rapid air flow will produce an almost perfect vacuum at'tliis low pressure area, the increasing rate of air flow causing the low pressure area to bc elongatcd somewhat after the form of a flame blown by an air current, the degree of vacuum diminishing in the extended portion, but the area of highest vacuum remaining always substantially at the same distance from the point of greatest. restriction of theVenturi, and substantially as shown by dotted line", 2:, in the drawing.

It is well understood that a vacuum fuel feed device of any of the types which have hithertobeen in use, that is, one in which the fuel is lifted from a low level by the suction of the engine, is subject to the defect that when the engine is running with wide open throttle and doing its heaviest work, and consequently requiring the largest amount of fuel to maintain the explosive mixture of the most effective proportions, the direct suction of the engine operating in the intake manifold 01- in the intake passage thereto is the lowest, and an automobile engine doing heavy work in climbing a steep grade, es pecially in high altitudes where the atmospheric pressure is low, is frequently unable to keep itself supplied with fuel because the vacuum is inadaquate to lift the fuel from the tank to the height of the carburetor, and in long stretches of such service the reserve of fuel accumulated n the reserve reservoir will become exhausted. On the other hand, as above indicated in the description of the characteristics of the Venturi tube with the wide open throttle, and consequent rapid inflow of air through the Venturi tube, the vacuum existing at the low pressure area, so, of the Venturi tube is increased by the freedom of the entrance of the air, causing large volume to move through the Venturi tube, which results in a relatively high velocity through the restricted Venturi throat. That is to say, otherthings being equal, the vacuum at the particular point referred to the low-pressure area of the Venturi tube, increases with the degree of opening of the throttle valve. It results that at the time when the direct suction of the engine is at its lowest. the throttle now being wide open, the suction or vacuum at the low pressure area of the Venturi tube gains from that same cause. On the other hand,vwhen the throttle valve 18 closedpr nearly closed, the suction, with the engine at any ivcn speed, is greatest and will serve to profuce the suction for lifting the fuel It is knownv from the low tank tothe elevated supplemental reservoir, aswell as for drawing it from the nozzle.

The structure illustrated takes advantage of these peculiar relations of suction or vacuum and air inflow, and thereby insures at all times an adequate suction to keep the elevated reservoir supplied from the low tank by the suction of the engine, said suction operating either directly, as when the throttle valve is closed, or through the effect of the rapid air inflow into the Vonturi tube when thethrottle is wide open.

The rise and fall of the float in the chamber, 7, opening the air inlet valve, 11, when the chamber, 7, has become filled to a predetermined height, and closing that valve when the liquid level falls, causing alternation of the domination of the suction operating through the restricted suction port, 9,

and of'the atmospheric pressure operating through the larger valve-controlled port, 10, causes the liquid lifted by suction to first fill the chamber, 7, and then discharge into the chamber, 8. Any of the other wellknown methods of effecting alternation of the domination of the atmospheric pressure and suction in the chamber, 7, for the same purpose may be employed. No claim is here made with respect to any particular method for producing this alternation. It is true, however, that when the method of producing the alternation which is here shown is employed,that is to say, having avalveless restricted suction aperture and a larger valved air port, the amount of air that is drawn into the manifold when the air valve is open, tending during the interval of emptying of the chamber, -7, to thin the mixture supplied to the en inc, operates somewhat to prevent that uni ormity in the quality of the mixture which is necessary to maximum economy in respect to fuel consumption. This defectniay be obviated to a large extent by the expedientpf providing a pan or use chamber, 211., which becomes filled with a liquid fuel'from. the liquid supply pipe, 6,

a serrated or slittedflange, 20, depending around the atmosphere inlet port, dipping into the liquid in the pan or touching the 115 surface with the points of the serrations, so

that the air which is drawn in through the atmosphere inlet port is, so to speak, fretted over the surface of the liquid, or even drawn through it if the flange, 20,'depends sufliciently into the liquid to make it necessary for the airto pass through the liquid in order to enter, and the air thus becomes coni tense of enrichment of the incoming air is increased by flaring the flange, 20, to approximately horizontal form and forming the serrations by narrow slits extending in the flared part as illustrated.

I claim:

1. In an internal combustion engine, in combination with a Venturi tube air intake, a low level fuel supply tank, a supplemental reservoir which constitutes the source of sup ply to the engine, a chamber from which. the liquid fuel is delivered by gravity into said supplemental reservoir, and a duct from the upper part of said chamber leading to and opening Within the Venturi tube at a point therein removed from the wall thereof and relatively near the axis of the tube.

2. In an internal combustion engine, in combination with a Venturi tube air intake, a low level fuel supply tank, a supplemental reservoir which constitutes the source of sup supplemental reservoir, a ductfrom the upper part of said chamber leading to and opening Within the Venturi tube at a point therein removed from the wall thereof and relatively near the axis of the tube, and

means in said chamber for alternatirf the domination of atmos heric pressure an suction through said not.

3. In a construction such as Set out in claim 2 foregoing, the means for efiecting such alternation of domination, consistin of a continuously open suction port an a valved atmosphere port, the latter being large relatively to the former; a float in the chamber operating to openthe atmosphere valve by the rise of the float, the atmosphere port. having a dependin flange, and a trap chamber into which sai flange depends-positioned for bein filled by thoiniow of the 7 liquid. s

4. In a structure such as set out in claim 3 foregoing, the lower margin of the depending flange being serrated.

5. In a structure such as set out in claim 4:

foregoing the flange being flared to approximately horizontal form and having the serrations formed by narrow slim in the flared part,

In testimony whereof, I; have hereunto set my hand at Chicago, Illinois, this 27th day of June, 1917.

onsnnns s; BURTON.

Images