US2015709A - Carburetor - Google Patents

Description

M. E. CHANDLER GARBURETOR Filed Oct. 5, 1931 2 Sheets-Sheet 1 r L M W .T mm a I 5% m W W WQ 9 4 Ma v/ 4 Y 4+ f n/o w k)! 33 x 2 M 3 1.

ATTORNEY Oct. 1, 1935 7 M. E. CHANDLER OARBURETOR Filed Oct. 5, 1931 2 sheets-sheet 2 49 86 INVENTOR.

' MWon 5.- Chandler 84 y 4 Q 915- ATTO Patented Oct. 1, 1935 2,015,709 CARBURETOR Milton E. Chandler, South Bend, Ind., assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application pctober 5, 1931, Serial No. 566,934

3 Claims.

This invention relates to charge forming devices, and more particularly to carburetors for internal combustion engines.

An object of the inventionis to provide an improved carburetor, the parts of which may be readily assembled and which will be eflicient in operation.

A feature of the invention is the provision of an air horn disposed at an acute angle to the venturi to produce a more even distribution of theincoming air.

Another feature of the invention resides in an arrangement whereby the venturi, main jet, pump, idler, bleeder tube, and economizer valve assembly may all be inserted into the body of the carburetor without changing the position thereof.

A further feature of the invention resides in an improved vent for the float chamber.

Further objects and advantages of the invention will be apparent from the following description, taken in connection with the appended drawings, in which:

Figure 1 is a vertical section through a carburetor embodying the invention, corresponding to a section on the line l| of Figure 3;

Figure 2 is a vertical section through the float chamber, corresponding to a section on the line 22 of Figure 3;

Figure 3 is a plan view of the carburetor;

, Figure 4 is a sectional view taken on the line 4-4 of Figure 3 and also corresponding to a section taken on the line 4-4 of Figure 1;

Figure 5 is a detailed sectional view through the air vent; and

Figure 6 is a sectional view taken on the line 6-6 of Figure 3.

Referring more particularly to. the drawings, a carburetor is shown comprising an upper casting or member I forming a carbureting chamber l 2, and -a lower casting or member I4 forming an air horn I 6. It will be noted that the axis'of the air horn is inclined downwardly atan acute angle to the axis of the carbureting chamber, for the purpose of providing a more even flow of air upwardly through the-carbureting chamber. This arrangement also results in the provision of a sump at l8 where excess fuel may. collect to be evaporated or, if desired, drained out through a port 2|] and drain tube 22. A choke valve 24 of any suitable construction is mounted in the air horn, and is preferably provided with a pressure actuated relief valve 26.

The lower member I4 is formed with an annular recess 28 upon which seats an annular flange 30 of the venturi 32, which is held in position by the upper member ID and also by one or more dowel pins 3|. The venturi has its upper portion accurately fitted within the carbureting chamber I 2 and has a depending flange 34 which is of smaller diameter than the shoulder 28 so that the venturi may be inserted from above in the assembly of the carburetor. The venturi above flange 30 has a curved surface which cooperates with the inner wall of chamber l2 to form an air passage 33 ex? tending around the venturi andcommunicating with the air horn by a plurality of vertical slots 35 (see Figure 6), for a purpose to be described hereinafter.

The carburetor is provided with the usual throttle valve 36 the actuating means for which, and for the choke valve 24, are indicated generally at 31 but are not described in detailsince they may be of any usual or desired construction. A float reservoir 38 is formed integral with member M with a cover therefor formed integral with the member In, a gasket 40 being interposed between the two. Any suitable means such as a float 4i acting upon an inlet valve 42 may be provided to control the flow of fuel through the fuel intake conduit 43 to thereby maintain the fuel in the float reservoir at the desired level.

Seated in a boss 44 projecting into the air horn is the main nozzle 46, the outlet end of which is centered with respect to the venturi 32. The nozzle stem 48 is threaded at its lower end into a bore 49 formed'in the-boss, and is provided with a longitudinal slot 50 closed at its upper end by a gasket 5| and communicating by means of ports 52 with the bore of the nozzle to provide an bleeding of the nozzle as described more fully hereinafter. A removable plug 54 is threaded. into a horizontal bore formed below the float reservoir and has a bore communicating with the float reservoir and with bore 49 and provided with a restricted portion 56 serving as a. metering orifice for the main nozzle. v v

The slot 50 communicates with a vertical bore 62 in which is threaded a sleeve 64 having a restricted passage at its lower end for the passage of fuel to the idling discharge holes 66 and 61,- which are closed against atmosphere by a thread-' t ed plug 69. Adjacent its upper end the bore 62 is enlarged and communicates with a transverse bore 68 leading to the carbureting chamber immediately above the venturi, and an adjustable .needl e valve 10 is mounted in bore 68 to control the air bleeding of the idle discharge holes and thereby controlthe rate of flow'of fuel through said holes. r

Within the float reservoir is provided an ac- 2 celerating pump which may be of the construction disclosed in the application of Don Cole, Serial No. 189,983, filed May 9, 1927, and comprising an inverted cup 12 actuated upon movement of the throttle valve 36 through a rod 14, and having therein a spring-pressed piston." slidable on a stud 18 having a bore communicating at its upper end with the interior of the cup 12 and at its lower end with a bore 62 communicating through bore 49 with the main nozzle 46. A threaded plug 84 having a metering restriction therein is interposedbetween bores 82 and 49, and beyond the threaded plug is a duct 86 which leads from the economizer, which is described below.

The economizer is located within the float reservoir and comprises a plug 88 having a duct 89 therein communicating with bore 86 and controlled by a spring-pressed valve member 90 having a vertical stem projecting above the plug 88. A cylindrical recess 92 is formed in member I0 directly above valve 90 and communicates by means of a duct 94 with the carbureting chamber I2 above the throttle. A piston 96 is mounted in recess 92 to be actuated by the suction through duct 94, and has fixed thereto a plunger 98 which is reciprocably mounted in a plug I00 and urged downwardly by a compression spring I02. The recess 92 is provided with a vent I04 which may open to atmosphere, but which in the preferred embodiment communicates with the passage 33 and through slots 35 with the air horn. The other end of vent I04 opens into recess 92 adjacent a series of slots I06 formed in plug I00, so that when piston 96 is in its lowermost position atmospheric pressure through vent I04 may still act upon its under surface to raise it against the force of spring I02. This economizer is more specifically described and claimed in my copending application, Serial No. 566,925, filed October 5, 1931.

A vent from the float reservoir is provided at I08, and a vertical passage I I0 is provided which communicates through passage I I2, with the slot 50 to provide air bleeding of the main jet through ports 52.

A sleeve II 4'is mounted in passage H0 and is provided with a restricted orifice to limit the amount of air flowing therethrough. The passage I08 also communicates with the float reservoir through an opening II5 which is so related to the inlet of tube II4 that the suction acting through the tube does notaffect the pressure within the float reservoir.

In operation, assuming the 'parts to be in the position shown in Figure 1, the throttle is opened and the engine is cranked, a limited amount of air being admitted through valve 26, which is mixed with a relatively large amount of fuel from nozzle 46, augmented by a charge brought by the acceleration pump and from the economizer, the valve 90 of which is at this stage open. The slot 50, at the time of starting, is filled with fuel and constitutes a starting or accelerating well, with the result that the ports 52 do not function as air bleed passages until the motor has begun to fire. When the motor begins to fire. choke valve 24 is of course opened and the air flows though the air horn downwardly and is deflected through an acute angle by the air horn, 5

reaching the venturi 32 without objectionable cross currents which would tend to deposit the fuel on the walls of the carbureting chamber.

It will be noted that in assembling the carburetor, the main nozzle 46, idling sleeve 64, venturi 10 32, and economizer valve and plug 88 may be inserted from above without changing the position of member I4, which facilitates the efflcient production of the device.

While a specific embodiment of the invention 15 has been described, it is not my intention to limit the invention thereto, or otherwise, except by the terms of the following claims.

I claim:

, 1. A carburetor comprising a lower body member forming an integral air horn and float reservoir, and an upper body member forming an integral carbureting chamber and cover for said reservoir,- a throttle in said chamber, a recess in said cover communicating with said air horn and said chamber above said throttle, an economizer valve in said reservoir, and means to actuate said valve slidably mounted in said recess and responsive to the difference in pressure in said A chamber and said air horn.

2. A carburetor comprising a lower body section forming an integral air horn and fuel reservoir, an upper body section forming an integral carbureting chamber and fuel reservoir cover, said air horn communicating with the carbureting chamber at an acute angle, a throttle in said chamber, a throttle .actuated acceleration pump having a reciprocating member in said fuel reservoir, an economizer valve in the fuel reservoir, pressure controlled actuating means carried by 40 the fuel reservoir cover to actuate the economizer valve, connecting means between a. portion of said actuating means and the carbureting chamber posterior to the throttle valve, and connecting means between another portion of said ac- 45 tuating means and the carbureting passage anterior to the throttle valve.

3. A carburetor comprising a lower body section forming an integral air horn and fuel reservoir, an upper bodysection forming an integral 50 carbureting chamber and fuel reservoir cover,

said air horn communicating with the carbureting chamber at an acute angle, a throttle in said chamber, a throttle actuated acceleration pump having a reciprocating member in said fuel reservoir, a vacuum actuated economizer valve in the fuel reservoir, an idling fuel passage issuing from the fue1.reservoir and discharging into the carbureting chamber through two spaced apertures on opposite sides of the throttle valve, and adjustable air bleed control means positioned in the idling fuel passage and regulating the rate of fuel flow for idlingpurposes.

MILTON E. CHANDLER.

CERTIFICATE or CORRECTION. Patent No. 2.015, 709..

MILTON E. CHANDLER.

October 1, 1935.

It is hereby certified that error appears in the printed specification of th above numbered patent requiring correction'as follows: Pagel, first column, line 40, for "566,925" read 566,935; and second coiumn, tine 4, for "though" read through; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 19th day of November. A. D. 1935.

Leslie Frazer (Seal) Acting Commissioner of Patents.

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