US2101536A - Fuel feed means - Google Patents

Description

Dec. 7, 1937. cso 2,101,536

- FUEL FEED MEANS Filed Aug. 19, 1956 2 Sheets-Sheet 2 INVENTOR.

Qeoge E. Ericson.

ATTORNEY.

Patented Dec. 7, 1937 UNITED STATES PATENT-E OFFICE.)

FUEL FEED 1 MEANS George It. Ericson, St. Louis, Mo., assignor to Carter Carburetor Corporation, St. Louis, Mo., a corporation of Delaware Application August 19, 1936, Serial No. 9 ,791

4 Claims.

This invention relates to fuel feed devices and consists, particularly, in novel means for supplying combustible fuel to an intake passage from an adjacent tank.

Charge forming devices for small stationary engines are frequeiltly carried on top of a fuel trolling needle valve several times before the tank is emptied.-

An object of the present invention'is to provide fuel "feed means for charge forming devices of the above type constructed to overcome the above-mentioned leaning out effect due to .empty- 'ing of the fuel tank.

Another object is to provide novel means for drawing fuel from a tank to a charge forming device under substantially uniform conditions.

These objects and other more detailed objects hereafter appearing are attained substantially by the structure illustrated in the accompanying drawings, in which:

Figure 1 is a vertical sectional view of a device illustrating the invention.

Figure 2 is a substantially diminished top view of the charge forming structure.

1Figure3 is a view similar to Figure 1, but illustrating a modification.

Figure 4 is a detail view similar to Figures 1 and 3 but showing still another form..

In Figures 1 and 2 is shown a tank I for gasoline or other combustible fuel and having a top portion 2 with a central aperture3. Secured in aperture 3 is a cup 4 having an overflow orifice 5. Mounted above cup 4' is a carburetor or charge forming device,'conveniently formed as a die casting, including barrel 6 forming a venturi I, and an air inlet portion 8 havingone or more holes 9 controlled by cup-like inlet valve Ill. The opposite end of the carburetor is longitudinally split as at I and provided with ears l2 for attachment to a tube or pipe I 3 leading to the engine intake (not shown), pressure being supplied to the ears for gripping tube i3 by a bolt l4.

: Depending from the carburetor barrel is the base structure [5 flanged as at It for attachment to the top of the tank immediately above cup 4 and apertured as at IT and [8. The en.- larged lower portion of aperture I1 is threaded for receiving a'nipple l9 which extends downwardly into cup 4 beneath, the level of over-flow hole 5. The lower portion of aperture l8 threadedly mounts an elongated tubular member '20 extending through cup 4" and downwardly into 5 the tank I; Member 20 has an enlarged chamber M in its lower portion'communicating with the tank through an inlet orifice 22 'controlled by check '23. A chamber 24 in .lateral projecting structure 25 communicates with pumping chaml0 'ber 2| through a hole 26 and with cup 4 through a tube 2! controlled by outlet check 28, Chamber 24 is closed at the bottom by screw'plug'29. Loosely received in the longitudinal passage 30 extending through tubular member 20, is. a rod 3| 16 carrying a piston 32 slidable in passage I8 and ex--'. posed to pressure conditions within the mixing chamber 33 of the carburetor. Piston 32 is v urged upwardly by a compression spring 34.- At

the lower end of rod .3! is a secondpiston slidable in pumping chamber 2| and constantly urged downwardly by a spring 36, which is somewhat stronger than spring 34 associated with the upper. piston. Rod 3| and pistons 32 and 35 thuslfl oat on springs34 and 36. 25

Carbureting devices, as described, are ordinarily used in connection-with one cylinder; stationary engines, during the operation of which pressure conditions within the mixing chamber of the carburetor are subject to substantial, 30 rhythmic variation. Such. pulsations cause pis tons 32 and 35 and connecting rod (to oscillate, intermittingly drawing fuel through the check controlled inlet 22 and discharging the same past outlet check 28 and through tube 27 into the 35 over-flow chamber formed by a cup 4. The ca-' pacity of the pump is suflicient to maintain liq uid fuel in the over-flow chamber at the level of the over-flow orifice 5, irrespective of the depth of fuel in the tank; so long as inlet 22 is im. 40 mersed. Thus liquid fuel will be drawn through nipple -l8 and aperture ll under substantially uniform pressure conditions; regardless of the I height" of the fuel in the tank. proper and, accordlngly; the fuel control needle 36 and air valve I0 need not be readjusted after being once set piston 39 and plunger 41 to oscillate, intermittingly drawing fuel past inlet check 46 into the pumping chamber 45 and expelling the same upwardly from the chamber 45 past collar 49 and through passage 48 into the over-flow chamber. During upward movement of plunger 41, collar 49 rests against shoulder 5| in the cap so as to substantially restrict downward movement of liquid from passage 48 into the pumping chamber, thus permitting a supply of liquid to be drawn in from the main tank. During downward movement of the plunger, check ball. 46 seats and collar 49, which fits loosely within the cap member 44, is lifted by the pressure of fuel-in the pumping chamber permitting the liquid to escape freely into tubular member 43 and the over-flow chamber.

In Figure 4, the loose collar, as at 49in Figure 3, is omitted, and plunger 41 in tubular member 43 cooperates with inlet check 46 in cap 52 to pump fuel into the over-flow chamber.

In Figures 3 and 4, as in the previous form, the capacity of the pump is such as to maintain liquid fuel within the auxiliary chamber at the level of the over-flow orifice so that fuel will'be supplied through induction passage under substantially uniform conditions.

The specific form of the pistons 32, 35, 39 and 41 may be substantially modified, and the use of diaphragms or other equivalents of a piston is contemplated. .In the present instance, the constant level fuel supply chamber 4 is mounted di rectly in the main fuel supply tank so that the use of a large capacitypump with an over-flow passage 5, 42 is quite satisfactory. The constant level chamber may be mounted outside of the main tank, where it is inconvenient to provide a return line, or the ordinary float controlled inlet valve, which is conventional in automotive carburetor constructions, may be used, if desired, to control the flow of fuel through the passages 21 or 43 from the pumping device to the constant level chamber.

The structure shown may be varied in these carried by said tank including a carburetor mix-- ture passage, a constant level chamber adjacent said passage, a suction fuel feed communication between said passage and said chamber, a pump having actuating means exposed to pressure conditions in said mixture passage, a pumping chamber and a check valve controlled inlet therefor near the bottom of said tank, and a duct connecting said constant level and pumping chambers.

2; The combination of elements specified in claim 1 in which said carburetor mixture passage is mounted on top of said tank and said constant level chamber is located inside said tank.

3. In combination, a fuel tank and structure carried adjacent the same comprising an induction carbureting passage, 9. tubular member extending from said passage downwardly into said tank, suction and pumping chambers, respectively, at the top and bottom of said member, a plunger extending through said tubular member between said chambers, valve means associated with said pumping chamber whereby liquid is forced through said tubular member upon pulsation of said plunger, a constant level chamber adjacent said induction passage and constructed and arranged to receive fuel from said tubular member, and a fuel feed conduit between said constant level chamber and said induction passage.

4. In combination, a carburetor for support on a fuel tank and having an inductionpassage, tubular structure projecting from said carburetor for insertion into the tank, a plunger extending loosely through said structure and exposed at one end to pressure pulsation in said carburetor, said tubular structure having a pumping chamber at its opposite end with a check controlled'inlet, an outlet valve seat spaced from said inlet, a collar loosely surrounding said plunger and cooperable with said outlet seat to substantially resist passage of fuel through saidseat except outwardly of said pumping chamber, an over-flow chamber adjacent said carburetor and communicating with said pumping chamber through said tubular member, and a suction fuel feed communication between said over-flow chamber and said induction passage.

GEORGE R. meson;

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