US2679388A

US2679388A - Carburetor

Info

Publication number: US2679388A
Application number: US340724A
Authority: US
Inventors: Rector Enoch
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-03-06
Filing date: 1953-03-06
Publication date: 1954-05-25
Anticipated expiration: 1971-05-25

Description

E. RECTOR May 25, 1954 CARBURETOR 2 Sheets-Sheet 1 Filed March 6, 1953 j mfi f 2 a .23 2 7 5 $2 INVENTOR. Enoch Fecior E. RECTOR CARBURETOR May 25, 1954 Filed March 6, 1953 \NrKk 2 Sheets-Sheet 2 INVENTOR.

Enoch Reefer i g m Patented May 25, 1954 UNITED STATES PATENT OFFICE CARBURETOR Enoch Rector, New York, N. Y. Application March 6, 1953, Serial No. 340,724

4 Claims.

This invention relates to carburetors of the vacuum feed type.

The principal object of the present invention is the provision of improved means in a carburetor of the indicated character for varying the amount of vacuum in the fuel chamber of the carburetor to control the amount of liqued fuel flowing from the fuel chamber to the mixing chamber of the carburetor, in order to obtain a fuel mixture of various proportions of air and gasoline for starting, idling, acceleration and power demands.

A further object of the invention is the pro vision of a dual valve connected with the throttle and operated in response to the usual operation of the throttle to meet diiferent engine requirements.

The present invention achieves the following results. When the throttle is closed, a comparatively rich mixture is provided for starting the engine and also for enabling the engine to idle. Upon operation of the throttle for acceleration, a quantity of air is admitted into the float chamber above the gasoline level therein, causing a reduced amount of vacuum in the float chamber with a corresponding increase of pressure in said chamber. As a result there is an increased flow of gasoline from the fuel jet, and vapor from the float chamber, which are available for variations in acceleration. As the throttle is opened wider more air is admitted to the float chamber with a proportionate increase in gasoline, thereby providing a somewhat leaner mixture for high speed. When the throttle is wide open a maxi mum amount of air is admitted to the float chamber with a proportionate increase in the amount of gasoline to the mixing chamber. All operations of the throttle produce variations in the amount of vacuum in the float chamber with corresponding variations in the amount of gasoline to meet different engine requirements for power and speed.

The nature of the invention and its distinguishing features and advantages will appear when the following specification is read in conjunction with the accompanying drawings, in which Fig. 1 is a vertical sectional view of a carburetor embodying the features of the present invention, portions being shown in side elevation.

Fig. 2 is a detail side view showing the operating connection between the throttle and the vacuum and liquid fuel valve means.

Fig. 3 is a sectional view taken on the line 3--3 of Fig. 5.

Fig. 4 is an enlarged vertical sectional view of the vacuum and liquid fuel valve means, the parts being shown in the relation they assume when the throttle is closed.

Fig. 5 is a view similar to Fig. 4, but showing the relation of the parts when the throttle is partly open.

Fig. 6 is a view similar to Fig. 5, but showing the relation of the parts when the throttle is wide open.

The carburetor as shown by way of example in the drawings has a hollow body or bowl I 9 with a lateral extension ll providing a circular liquid fuel chamber [2 and a space l3 in communication therewith. The bowl I!) has a removable dome shape top cover l4 and a flanged base I5.

Centrally of the bowl I0 is a venturi l6 composed of sections fitting in the lower end of a tube l1 forming a main down draft air intake passage and a mixing chamber [8 in conjunction with the base I5. It is to be understood that the flange of the base [5 will be secured to an engine intake manifold to establish communication of the carburetor with an engine of the internal combustion type.

The venturi [6 has a plurality of passages or jets l9 which communicate with the mixing chamber l8 and also communicate with an annular space 20 which in turn communicates with a passage 2! in the bottom of the bowl extension I l. The bowl I 0 has a jet 6 which establishes communication between the chamber l2 above the fuel level and the mixing chamber 18.

An annular float 22 is arranged in the chamher I 2. The float has a lever 23 which is fulcrumed on the extension H, as at 24. The lever 23 has a rounded end portion 25 disposed between parallel flanges 26 on the stem 2'! of a conical valve member 28 on the lower extremity of the stem. A tubular member 29 has its lower end screwed into a tapped hole in the bottom of the bowl extension II, and its upper end is received in a cap nut 30 screwed into a tapped hole in the cover I4. Thus the tubular member 29 is fixedly secured and disposed vertically in, the space E3. The nut 30 has a depending tubular guide 3| which loosely receives the stem 21 so that the latter may have up and down sliding movement. For this purpose the guide 3| extends downwardly into the upper end portion of the member 29. The bore 32 of said upper end portion is larger than the bore 33 of the lower end portion of the member 29. This provides a shoulder which constitutes a valve seat 34 with which the valve member. 28 cooperates. The

member 29 has an outlet port therein which communicates with the bore 32 and the space l3. The bore 33 serves as a gasoline inlet duct. A gasoline feed pipe 35 is connected with the member 29 in communication with the bore 32 by means of a nipple 31. It will now be understood that there has been described a valve, operated in response to the rise and fall of the float 22, which controls the admission of gasoline into the chamber l2.

In accordance with the principal feature of the present invention there is provided an air and gasoline control valve which is operatively connected with the throttle valve operating means 38, which latter is cooperatively connected with a dash pot or pump 39 communicating with the chamber l2.

The aforesaid dual control valve includes an outer tubular member 40, an inner tubular mem-' ber 4| and a valve stem or metering pin 42. The tubular member 48' has an air inlet port 43, a plurality of air outlet ports" 44, a plurality of gas-- oline inlet ports 45, and gasoline outlet ports 46. All of said ports open through the interior sur face of the tubular member 40.- A jet 41 is secured or formed the-tubular member to es tablish communication between the ports 45 and the ports 46 by virtueo'f the hollow of the lower reduced end portion 48 ofthe tubular member 4|). 0

Said end portion 48 fits in a hole in thebottom of the extension II, and is externally threaded to receive a cupped nut 49. The tubular member 45- extends through the cover l4 and is in threaded engagement with a nut 50 bearing on the cover M. The tubular member 40' is thus held stationary in a verticalposition. The port 43 is open to the atmosphere, the ports 44 communicate with the float chamber i2 above the gasoline level, the ports 45 communicate with the chamber |2 at the bottom thereof, and the ports 46 communicate with the passage 2|.

The inner tubular member 4| fits in the tu-- bular member 40 so as tobe slidable up and down with respect thereto. The tubular member 4|- has a plurality ofports 5|, and a reduced intermediate portion 52 with axially spaced sets of ports, there being an upper set of ports 53 and a lower set of ports 54 greater innumber than the number of ports 53. A portionof the tubularmember 4| directly above the ports 53 inthe por tion 52' constitutes a slidable valve member 55 which cooperates with the air outlet ports 44 td control the outflow of air from the valve'into the chamber l2. It will be apparent that the reduced portion 52 in conjunction with the tubular member 40 provides an annular air space 55 between the members 40 and 4|. The internal diameter of the upper end portion of the tubular member 40 is larger than the external diameter of the" tubular member 4|, thereby providing an annular air space 51 between the members 40 and 4|, said space 51 being completed by a gland nut 58 threaded in the upper end of the tubular mem-' ber 49. The air space 51 is always in communi cation with the port 43 and ports 5|.

Referring to the stem or metering pin 42, it willbe seen that its lower extremity 59 is conical and its upper end has-an adjustable nut 60. The pin 42 is longer than the tubular member 4| through which it extends in coaxial relation thereto. The upper end portion 61 of the pin 42 is in threaded" engagement with the member 4|, and the lower end portion of the pin fits in the reduced bore of the tubular member 4|, and the major portion of the pin' 42 is disposed in the enlarged bore of'the' member 4|, providing a cylindrical air space 62 between the member 4| and pin 42. A helical spring 63 surrounds the upper end portion of the pin 42 and is interposed between the nut 60 and the upper end of the member 4|. The pin 42 is thus movable up and down with the member 4| and is axially adjustable with respect thereto so as to be set with its conical end 59 in different normal metering positions of adjustment with respect to the jet 41.

In order that the inner tubular member 4| and the pin 42 connected therewith move up and down in response to the operation of the throttle member'54, the aforesaid means 38 comprises a collar 65 clamped on the upper end of the tubular member 4|, and linkage 66 connecting the collar 55 with the arbor of the member 64, as shown in Fig. 2.

When the throttle is closed, air nevertheless is drawn into the main air intake tube H for starting the engine and also for enabling the'engin'e to idle. 'The parts of the dual valve are then in the relation shown in Fig. 4. Atmospheric air cannot pass through the valve into the chamber |2 because the outlet ports 44 are closed by the valve member 55. The conical end 59 of the stem 42 is in its minimum flow position in relation to the jet 41. Gasoline is drawn into the mixing chamber l8 from the chamber |'2 through the ports 45, jet 41, hollow of the member 4 l', ports' 46, passage' 2|, space 20,. and jets l9. The float 22 operates the valve stem 28 to maintain the gasoline at the predetermined fuel level in the chamber |2.

Upon operation of the throttle for'accelerati'on, the member 4| and the stem 42 are moved up-- wardly in unison, as indicated in Fig. 5'. This causes a gradual opening of the outlet ports 44 and a lifting of the conical end 59 farther from the jet 41. A quantity of air is admitted to the chamber I2 by way of the port 43, space 51, ports 5|, space 62, ports 53' and 54, space 55 and ports 44. This causes a reduced amount of vacuum in the chamber l2 with a corresponding increase of pressure in said chamber; Consequently therewill be an increased flow of gasoline through the jets |9 as well as a flow of vapor from the charli ber |2 through the jet 8 into the chamber I8. This increased flow of gasolineand the additional vapor are available for variations in acceleration. Conversely, the gradual d'ecreased-flowof gasoline and vapor are available for variation in decelera-' tion throttle operations.

When the throttleis'wide open as indicated in Fig. 6, a maximum amount of air is admitted to r the chamber |2 with a proportionate increase'inthe amount of gasoline from the jets l9 and vapor from the jet 6 to the mixing chamber |8 to meet difierent engine requirements for power and speed;

If desired, a hood 61 may be secured to the upper end of the tubular member 40 about the" air inlet port 43. The hood is omittedfrom Figs. 4, 5 and 6.

It is to beunderstood that the number and the size of the ports in the dual'valve maybe varied;

that the discharge area; of' the jet 6 is larger than the inlet area of the port 43, and that the present invention" includes; all other constructions and modificationscom ing" within the scope of the appended claims.

I claim:

1. In a carburetor, a liquid fuel chamber, a: valve including a statio'nary out'e'r tubular mem ber and an inner tubular member having axial movement within said outer tubular member;

said outer tubular member having a reduced portion providing an upper annular air space between said tubular members, said outer tubular member having an air inlet port communicating with said upper air space, said outer tubular member having air outlet ports communicating with said fuel chamber, said inner tubular member having upper ports which communicate with the interior of the inner tubular member ing such that the inner tubular member closes the air outlet ports of the outer tubular member in the full down position of the inner tubular member, thereby preventing a flow of air through the valve, and that said inner tubular member opens said air outlet ports of the outer tubular member to the lower air space in all partly up and fully up positions of the inner tubular member, thereby allowing metered quantities of air to flow through the valve into said chamber.

2. In a carburetor as set forth in claim 1, and throttle operating means connected with said inner tubular member to cause the axial movement of the latter.

3. In a carburetor, a mixing chamber, a float chamber, a jet establishing communication between said chambers above the fuel level of said float chamber, a fuel passage leading into said mixing chamber, and a dual valve operable to control the flow of air into said float chamber so as to control the amount of vacuum in said float chamber, and to meter the flow of fuel in said fuel passage subject to the amount of vacuum,

said valve including a stationary outer tubular member and an inner tubular member having axial movement within said outer tubular member, said outer tubular member having a reduced portion providing an upper air passage between the outer and inner tubular members, said outer tubular member having an air inlet port communicating with said upper air passage, said outer tubular member having air outlet ports communieating with said float chamber, said inner tubular member having upper ports which communicate with the interior of the inner tubular member and said upper air passage, said inner tubular member having a reduced portion providing a lower air passage between the outer and inner tubular members, said reduced portion of the inner tubular member having axially spaced ports which communicate with said lower air passage and the interior of the inner tubular member, said outlet ports of the outer tubular member communicating with said lower air passage, the provision and arrangement being such that the inner tubular member closes the air outlet ports of the outer tubular member in the full down position of the inner tubular member, thereby preventing a flow of air through the valve, and that said inner tubular member opens said air outlet ports of the outer tubular member to the lower air passage in all partly up and the fully up positions of the inner tubular member, thereby allowing metered quantities of air to flow through the valve.

4. In a carburetor as set forth in claim 3, and means operated by the movement of said inner tubular member for metering the flow of fuel through said fuel passage.

References Cited in the file of this patent UNITED STATES PATENTS