US2485525A - Liquid-control and deaerating device - Google Patents

Description

Oct. 18, 1949. P. w. BEDALE I 2,485,525

LIQUID CONTROL AND DEAERATING DEVICE Filed Oct. 22, 1945 Patented Oct. 18, 1949 LIQUID-CONTROL AND DEAERAIIING DEVICE Paul Whibley Bedale, Littleover, Derby, England,

assignor to Rolls Royce Limited, Derby, England, a British Company Application October 22, 1945, Serial No. 6235615 In Great BritainJulyB, 1944 4 Claims. (01. 1832.5)

This invention relates to-liquid-control and deaerating devices for internal-combustion engines, of ,thelkind in which liquid fuel is delivered to a supply chamber through a port that is controlled by a valve and the valve is actuated by a diaphragm that is subjected to the pressure within the supply chamber and, in opposition to the diaphragm, by a centrifugal governor arranged to be driven from the engine so that the pressure within the supply chamber is maintained proportional to the square of the engine speed. Fuel leaves the supply chamber through one or more jets which are adjusted in accordance with the pressure and temperature in the engine induction manifold in such manner that the rate of fuel supply to the engine is a function of the mass flow of air to the engine and the fuel-air ratio of the combustible charge is maintained constant or suitably varied.

The object of this invention is to provide means for de-aerating the fuel delivered to the supply chamber of the carburettor.

According to therpresent invention a carburettor of the type indicated comprises a centrifugal governor arranged in an ante-chamber through A which the fuel passes to the supply chamber and causing by its rotation fuel to circulate by centrifugal action between the ante-chamber and a float chamber connected thereto and also causing by centrifugal action separation of air and vapour from the fuel, the arrangement being such that when the amount of separated air and vapour accumulated in the ante-chamber exceeds a certain amount the circulation between the ante-chamber and the float chamber temporarily ceases and the outlet valve of the latter chamber opens and allows escape of air and vapour therethrou'gh after which the circulation between the ante-chamber and the float chamber is re-established.

The ante-chamber is connected to the float chamber by two passages of which the openings into the ante-chamber are at different radial distances from the rotational axis of the centrifugal governor.

The duct in the ante-chamber which leads to a valve controlling the supply of fuel to the supply chamber opens into the ante-chamber at a greater radial distance from the axis of the governor than the passages connecting the antev.

the antechamber when the outlet valve in the float chamber is open.

The above and other features of the invention will now be described with reference to a non-limitative embodiment as illustrated in the accompanying drawing which shows a longitudinal section of the embodiment.

' In this embodiment a centrifugal governor l is mounted in an ante-chamber 2 through which fuel passes on its way to the outlet port 3 which opens into a supply chamber 4. The ante-chamher 2 communicates with the port 3 through the duct 5 of which the end 6 is spaced radially from the axis of rotation of the governor l. Passages l and 8 connect a float chamber 9 with the antechamber 2, the float chamber having an outlet ill to a fuel supply'tank, and the outlet being controlled by a float-operated valve H. The ends 12 and I3 of the passages l and 8 are spaced radially from the rotational axis of the governor i and from each other and these ends are spaced from the axis of the governor by radial distances therefrom which in each case is less than the radial distance between this axis and the end 6 of the duct'51 The ante-chamber 2 is fitted with a springloaded relief valve I4 which is carried by a diaphragm 1T5, and'a rotary pump I6 draws fuel through the inlet pipe I! and delivers it into the ante-chamber 'z'through the duct l8. Fuel dischargedb'y'the relief valve l4 passes into the inlet pipe 11 and is returned to the ante-chamber 2 by the pump Hi.

In the above arrangement, the rotation of the centrifugal governor l within the ante-chamber 2 causes the fuel therein to rotate about the axis of the governor so that any air and vapour in the fuel are separated out by centrifugal action and collect around the governor axis, while deaerated fuel flows from the ante-chamber 2 to the supply chamber 4 through the duct 5 and port 3. The pressure of the fuel in the ante-chamber 2 increases radially outwards owing to centrifugal action so that the passage 8 leading to the float chamber 9 is subjected to a higher pressure than the passage 1 and the fuel will accordingly circulate from the ante-chamber through the float chamber and back to the ante-chamber to maintain the float chamber full of fuel so that the outlet ID from the float chamber is closed by the float-operated valve l I. When sufiicient air and vapour has collected in the ante-chamber 2 to uncover both of the passages l and 8 to the float chamber 9, the circulation of fuel through the float chamber will cease and air or vapour will enter it. The float-operated valve II will then open the outlet It so that the air and vapour in the float chamber 9 can escape. The springleaded relief valve 14 serves to maintain the pressure within the ante-chamber 2 at a predetermined pressure above atmospheric pressure so that the opening of the outlet from the float chamber 9 will result in part of the accumulated air and vapour in the ante-chamber being expelled through the outlet It by the excess pressure within the ante-chamber. This will, in turn, allow of the raestablishment of the fuel circulation through the float chamber 9 and the cycle will be repeated indefinitely.

It should be noted that the disposition of the passages l and 8 leading to the float chamber 9 and the duct leading to the supply chamber 4 is such that the duct 5 will always be covered by fuel so that there is no possibility of air entering it. The passage 1 should open into the antechamber 2 as near the axis of the governor l as possible. i

I claim:

1. In :a liquid-control and de-aerating device, the combination of a supply chamber, an antechamber having a duct through which fuel passes to said supply chamber, a fuel inlet to said antechamber, means for controlling the supply of fuel from said ante-chamber to said supply chamber, a centrifugal governor in said ante-chamber operatively connected to said fuel controlling means, a float-chamber having an outlet and having passages from it opening into said ante-chamber at points radially Spaced from the rotational axis of said governor and from each other and radially spaced at a less distance from said axis than that of said fuel duct therefrom, a float-operated valve in said float chamber controlling said outlet therefrom to permit the escape of air and vapour sepa-. rated from said fuel b centrifugal action arising from the rotation of said governor.

2. In a, liquid-control and de-iaerating device, the combination of a supply chamber, an antechamber having a duct through which fuel passes from said ante-chamber to said supply chamber, a fuel inlet to said ante-chamber, means for controlling the supply of fuel from said ante-chamher to said supply chamber, a centrifugal governor in said ante-chamber operatively connected to said fuel controlling means, a float chamber having an outlet and having passages opening into and said ante-chamber, said passages being radially spaced in said ante-chamber from the rotational axis of said governor and from each other and radially spaced at a less distance from said axis than that of said fuel duct therefrom, a floatoperated valve in said float-chamber controlling through said outlet the escape of air and valpour separated from said fuel by centrifugal action arising from the rotation of said governor together with means for maintaining said antechamber at a certain predetermined pressure greater than atmospheric pressure.

3. In a liquid-control and de-aerating device, the combination of an ante-chamber, a centrifugal governor rotatable therein, a fuel inlet to said ante-chamber, a fuel-outlet from said chamber remote from the axis of rotation of the governor, a passage from said fuel-outlet terminating in a port, a supply-chamber into which said port opens, a valve operated :by said centrifugal governor and controlling said port, two openings from said ante-chamber both situated nearer to the :axis of rotation of said governor than is said fuel-outlet, and one of said openings being nearer to said axis than the other, a float-chamber, passages from said two openings communicating with said float-chamber, a discharge orifice at the upper part of said float-chamber land a floatoperated valve controlling said orifice.

4. In a liquid-control sand 'de-aerating device according to claim 3, the combination with the ante-chamber of means supplying to it fuel under pressure and a spring-loaded relief-valve maintaining the fuel in the ante-chamber under pressure.

PAUL WHIBLEY BEDALE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,345,895 Seguin July 6, 1920 1,655,647 Hornbostel Jan. 10, 1928 1,906,334 Rathbun Ma 2, 1933 2,238,502 Muir Apr. 15, 1941 2,368,529 Edwards Jan. 30, 1945 FOREIGN PATENTS Number Country Date 526,988 Great Britain Sept. 30, 1940 630,932 Germany June 9, 1936

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