US2679387A - Carburetor - Google Patents

Description

E. RECTOR CARBURETOR 2 Sheets-Sheet 1 Filed Jan. 8, 1952 ii L4 G a w\ Tm mm mm v 2 b mm m L 4 Q Al, W E w n J m a? mm Hm mm R ll. Q N Wm Nm Q w W E E W wv mm m wm Nu m? v 3, mm 3 Iii 1 All mm mm mm .R i mm. mm vm m MP mm a R May 25, 1954 E. RECTOR CARBURETOR Filed Jan. 8, 1952 2 Sheets-Sheet 2 INVENTOR. 2720072 Heoibr BY MMYW Patented May 25, 1954 [TED .-'S TATE S "PAT-E NT OF FIG-E CARBURETOR EnochRec'tor, New Yor -N. Y. Applicationflanuary 8, 1952, Serial No. 265,421

Claims.

This invention relates'in generalto a carburetor of the vacuum airlift type, and has especial reference to improved meansv for.the.control of 'fuel feed pipe, as near as practicable above the levelofthe fuel inthe supply tank so as to-mix withthe air for the .purpose of delivering fuel to the carburetor.

It is therefore an object of the present invention to eliminate the fuel pump and its accessoriesfound to .be faulty and requiring repair and replacementfrom time-to time in connection with acarburetor for an internal combustion engine.

Another object of this invention is the provision of a reserve tank constituting a part of the carburetor of the indicated character, in which tank, the air and all fuel vapors are separated from the liquid fuel at the top of the tank and are delivered .to the top of a float operated fuel admission valve member while-the liquid fuel is delivered from the bottom of the tank into the float .chamber. This provides a balanced fuel admission valve means readily responsive for idling and for all running speeds of the engine and vehicle.

Another object of the invention is the provision of a fuel reserve tank of the character mentioned soas to provide a fuel supply above the fuel level in thefloat chamber, in extremecases, when the throttle valve is wide open or nearly so,-and the engine speed is very slow and the intake manifold vacuum is not sufficient to draw the fuel from the reserve tank. However, this condition occurs only momentarily, and as soon as the engine speed is increased to 800 revolutions, the vacuum will be sufiicient to draw fuel from the supply tank to refill the reserve tank to its normal capacity. Also. the reserve tank eliminates all possibility of a vapor look which occurs during very hot weather in all of the standard carburetors.

With the foregoing, other objects and advantages of the invention will appear when the following specificatioin is read in conjunction with the acccmpanyinp; drawings, in which:

Fig. 1 is a vertical sectional view, the section being taken substantially as indicated by the line I-l of ig. 2, and certain parts being shown inside elevation.

Fig.2 is a horizontal'sectional view taken substantially on the line 2-2 of Fig. 1.

Referring now' more particularly to the drawings, it will be apparent there is shown a. hollow body or bowl Hl'with a lateral extension providing a circular liquid fuel chamber l2 and space 13 in communication therewith. The'bowl I!) has a removable domed top cover I l and a'flanged base l5.

Centrally of the bowl i0 is a venturi [6 composed of sections fitting in the lower end ofa tube H forming'a main 'do'wn draftgpassage l8 and a mixing chamber in ejn uneaon with the base l5. It is to b'eunderst'ood that the upper end of the tube I! wil1havesuitab1e air, intake and that the base [5"w'ill'be secured 12. the engine intake manifold "in communication there'- with.

The venturi has a plurality of p sages or jets I9 which open into the passage flBfand also communicate with an annular space. 20 which communicates with a passage 2| in the bottom of the bowl extension .IL. g

A metering pin 22 is slid'able up anddown in a tubular guide 23. The lower end of the guide 23 has ports 24 and a plug -25. vThe ports 24 communicate with the interior ofth'e guide. The plug 25 has an outlet port ZGand'a-stud 27. The extension II and base It areinachinedto receive the plug so that the port 26 establishes communication between the interiorof the guide 23 and the passage 2|. The upper end of the guide 23 is threaded in the cover l4 and its outer upper extremity has a packing unit 28 Whichreceives the pin 22. The upper end of the pin 22 is operatively connected with the throttle valve operating means 29 which latter is also connected with a dash pot or pump 30 communicating with the chamber ii. The pin 22 cooperates with the port 26 to control the flowof gasoline from the chamber l2 tothe spray jets I 9 by way of the ports 24, and 26, passage 2! and space 20 in the order named. I H

An annular float 31 is arranged in the chamber l2. The float has a lever 32 which is fulcrumed on the extension I has at 33. The lever 32 has a rounded portion 34 disposed between parallel flanges 35 on the stem- 36 ofa conical valve member 31- on the lower extremity of thestem. A duct or passage 38 extends longitudinally through the stem and its valvemember; The valve member 31 cooperates with a seat 39-carried by a tubular guide 40 heldin place by a hollow threaded plug M and a bushing 42. a The plug 4i extends upwardlythrough the base 15 and the bottom of the extension ll in threaded engagement with said bottom and. the lower tapped endof'tl'iegu'id lll. The bushing 42'is in a bottom and a top 52.

threaded engagement with the reduced screw portion 43 of the guide. There are ports 44 in the guide above the seat 39. These ports 44 establish communication between the space i3 of the float chamber I2 and a passage 45 formed by the lower end portion of the guide 49 and the plug 4|.

The valve member 3'! with its stem 36 is balanced by pressure on its opposite ends, with the result that the varying vacuum pressure in the chamber 2 does not affect the fuel discharge, and a constant level of the fuel in the chamber I2 is maintained. The stem is machined a few thousandths of an inch smaller than the interior diameter of the guide 40 so that some air and gas vapor may leak through the guide 49 into the float chamber I2 as will more clearly appear hereinafter. Since there is no close tolerance fit of the stem 33 in the guide 40, the stem will not stick, but will be readily responsive to the movement of the float 3| in its control of the flow of fuel into the chamber l2 from the passage 45.

In accordance with another important feature of this invention, use is made of a fuel reserve vessel or tank 49 as a part of the carburetor. The tank 49 comprises a cylindrical side wall 50, The bottom 5| has a lateral extension 53 to provide an outlet passage 54 for the tank in continuation with the passage 45, it being apparent that the plug 4| projects upwardly through the extension 53. The top 52 has a lateral extension 55 to provide an air and gas outlet passage 59. A hollow plug 51 is threaded in a tapped hole in the extension 55 and is connected by a union 58 to the upper end of the guide 49. The plug 51 has ports 59 which communicate with the hollow 39 of the plug thereby providing a passage which establishes communication between the passages 38 and 56. Thus the interior of the tank has a continuous flow passage from the top to the bottom thereof.

A liquid fuel feed or inlet pipe 9| from a main supply tank (not shown) is connected with the bottom 5|. A riser tube 62 has its lower end screwed into a boss on the bottom 5| in communication with the pipe 9|. The upper end of the tube 62 has a depending circular flange 63 and a coaxial vent 64 above the flange. Ports 65 and 65 in the tube 62 and flange 63 respectively, establish communication between the interior of the tank 49 and the interior of the tube 52 and the vent 94. Filtering screens 6'! and 68 in spaced relation to each other engage circular shoulders 69 and ill respectively, on a depending circular flange formed on the top 52 at the inside thereof. A helical spring 12 surrounds the tube 62 between collars 13 and 14 on the tube 62 the latter having a shoulder for the collar 13. Each screen is of two semi-circular parts. The discharge ports 65 and 66 occur between the screens. A nut I5 screwed on the outer end of the vent 64 and bearing on the extension 55 helps to hold the top in place.

Liquid fuel and air lifted from the main supply tank flow upwardly through the pipe 6|, tube '52 and ports 65 and 63 into the tank 49. It is to be understood that the liquid fuel is lifted from the supply tank into the reserve tank 49 through pipes 6| and tube 62, by suction action induced within the tank 49 at the top thereof, and by reason of the fact that liquid flows from a lower level of a higher pressure in the supply tank to a higher level of a lower pressure in the reserve tank 49. The fuel in the tank 49 rises therein above the fuel level in the chamber l2. Thus a reserve supply of fuel is provided when, in extreme cases, the throttle valve is wide open or nearly so, and the engine speed is very low and the manifold vacuum is not sufficient to draw the fuel from the main supply tank. However, this condition occurs only momentarily. As soon as the engine speed increases to about 800 revolutions, the vacuum will be suflicient to draw fuel again and will refill the tank 49 to its normal capacity.

The air and gaseous fuel in the tank 49 above the level of the liquid fuel therein eliminates air lock. The air and gaseous fuel always present at the top of the tank 49 are drawn through the path formed by the passage 56, ports 59, hollow 60, passage 38, ports 44 into the top of the chamber 12 when the valve member 31 is open. This gaseous fuel is drawn into the main air passage IB through jets in tube l1 above the venturi is. Also some of this vapor may pass between the stem 36 and the guide 40 to the ports 44 just prior to the opening movement of the valve member 31. Thereafter, liquid fuel flows from the bottom of the chamber l2 to passage l8 while liquid fuel is fed into chamber |2 from the bottom of the reserve tank 49 through the intercommunicating passages 54 and 45 and ports 44.

The present invention is not restricted to the details above described, but includes all constructions and modifications coming within the scope of the appended claims.

I claim:

1. A carburetor of the vacuum air lift type having the combination of a body providing a float chamber adapted to contain liquid fuel, said body also providing a main air intake passage communicating with said float chamber, a fuel reserve tank having a fuel and air inlet means extending from the bottom to near the top, an air and gas outlet passage at the top of the tank communicating with said float chamber, and a fuel outlet passage at the bottom of the tank, a

- seat on said body surrounding the fuel outlet passage, a valve member having a stem mounted on said body for up and down movement between an open and closed position with respect to said seat, said stem having a passage communicating at its opposite ends with said outlet passages, said valve member controlling the admission of fuel into said float chamber from said fuel outlet passage and the amount of vacuum in said tank by reason of said air and gas outlet passage, a float 4 in said chamber responsive to the rise and fall of fuel in said chamber, and cooperative means on the stem and float by which the float moves the valve member for the stated purpose.

'2. A carburetor as set forth in claim 1, and a throttle operated valve to control the flow of fuel through an outlet passage leading from the float chamber to a mixing chamber.

3. A carburetor as set forth in claim 1, wherein said valve member is balanced by pressure on one end of the stem and one face of the valve memher.

4. A carburetor as set forth in claim 1, wherein 5. A carburetor as set forth in claim 1, wherein said fuel and air inlet means includes a riser tube extending from the bottom of the tank to.

near the top thereof, and the upper end of the tube has discharge ports therein.

6. A carburetor of the vacuum air lift type having the combination of a fuel reserve container, a body providing a float chamber adapted to contain liquid fuel, said body also providing a air intake passage communicating with said float chamber, a float in said chamber and having a lever fulcrumed on said body, an outlet passage leading from the interior of the container at the bottom thereof to the interior of said float chamber, valve means on said body operated by the lever of said float to control the flow of fluid through said passage to said chamber from said container and the amount of vacuum in said container, said valve means including a valve member having a stem, and intercommunicating passages leading from the top of said container into said valve member and its float chamber through said stem.

7. A carburetor of the vacuum air lift type having the combination of a body providing a float chamber adapted to contain liquid fuel, said body also providing a main air intake passage communicating with said float chamber, a fuel reserve tank, a liquid fuel and air inlet tube extending upwardly through the bottom of the tank to near the top of the tank, there being discharge ports in the upper end of the tube, said tank having an air and gas outlet passage leading from the top and a fuel outlet passage leading from the bottom, a seat on said body surrounding said fuel outlet passage, a valve member having a stem mounted on said body for up and down movement between an open and closed position with respect to said seat, said stem having a passage communicating at its opposite ends with said outlet passages, said valve member controlling the admission of fuel into said float chamber from said fuel outlet passage and the amount of vacuum in said tank, a float in said chamber responsive to the rise and fall of fuel in said chamher, and cooperative means on the stem and float by which the float moves the valve member for the stated purpose.

8. A carburetor as set forth in claim 7, wherein the ports of the inlet tube are so disposed within said tank that the level of the fuel in the tank will be above the level of the fuel in the float chamber.

9. A carburetor of the vacuum air lift type having the combination of a reserve fuel container, a body providing a float chamber and a main air intake passage communicating with said float chamber, said container having an outlet passage leading from its interior at the top and an outlet passage leading from its interior at the bottom thereof, and float operated valve means including a valve member having a duct extending longitudinally therethrougli responsive to the rise and fall of fuel in the float chamber to establish communication of said passages and the float chamber and also for disestablishing the aforesaid communication.

10. A carburetor of the vacuum air lift type having the combination of a reserve fuel container, a body providing a float chamber and a main air intake passage communicating with said float chamber, said container having an outlet passage leading from its interior at the top and an outlet passage leading from its interior at the bottom thereof, and float operated valve means responsive to the rise and fall of fuel in the float chamber to establish communication of said outlet passages with said float chamber and also for disestablishing the aforesaid communication, said valve means including a slidable valve member with a stem having a duct extending through the valve member and the stem, the opposite ends of said duct being in communication with said outlet passages respectively, when the valve means is closed, and the opposite ends of said duct being in communication with said top outlet passage and the float chamber respectively, when the valve means is open.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,313,925 Stewart Aug. 26, 1919 1,330,796 Gilles Feb. 17, 1920 1,399,530 Stewart Dec. 6, 1921 1,440,868 Crane Dec. 20, 1921 1,676,767 Burns July 10, 1928 1,815,485 Scott July 21, 1931 2,051,820 Chandler Aug. 25, 1936 2,138,592 Bracke Nov. 29, 1938 2,275,541 Meade Mar. 10, 1942

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