US2538559A - Combined carburetor choke and nozzle - Google Patents

Description

Jan. 16, 1951 w. E. EGERER COMBINED CARBURETOR CHOKE AND NOZZLE 2 Sheets-Sheet 1 Filed May 20, 1949 Jan. 16, 1951 w. E. EGERER COMBINED CARBURETOR cnom: AND NOZZLE 2 Sheets-Sheet 2 Filed May 20, 1949 Patented Jan. 16, 1951 omre r oolvrn m iin GARBURETUR necks 1 :NozzLE Detroit,-lt?lich. ,;as signor to Gedi ge M. Holley and'Earl Holley Application Mai/"20, mia sriairlio. 945446 'tcaiiss. fl

L object of this inven tion i s tpjmproye the fuel nozzle shown in the co-pendlng Kittler -& Winter application Serial No. 58,748 filed November 6,

94 c, line there is to make a choke valve serve also as the fuel nozzle of a plain tube ca l lh av'e discovered that if I use an annula rbutterfiy choke and discharge fuel into the centiifof thefannill us from the hollow shaft (seamen the'chokevalve'ismounted I will have e veiy gaasratteryfiler ozzle amen unsatisfactory eriekevaiv'e. "So I hen discovered that the hollow shaft which farms the stationary nozzle could'c'arry a'dis'c 'iipst'r'eam of the fuel outlet which disc could just obstruct the central opening of the annular choke valve when the choke valve was closed. I "would then have a still better fuel nozzle and the choke Valve would be satisfactory.

Fig. 1 shows the preferred "form of my inventio n"-:choke valve open. J n a t Fig. 2sna esaeressacti'anai elevation on the' plane 2-420} Figfl'throii'ghthechoke valve when thechokevalve'is'clhsd.

Fig. 3 is an exploded view showing how the choke valve is rotated.

Fig. 4 shows an alternative construction with the choke valve open.

Fig. 5 shows a cross-sectional elevation on plane 55 of Fig. 4 with the choke valve shut.

Fig. 6 shows a detail of the hollow stationary nozzle.

Fig. '7 shows an exploded view of the driving means for the choke valve.

Fig. 8 is a cross-sectional plan view on the plane 88 of Fig. 6.

In the Figure is the air entrance, [2 is the choke valve located in the throat of the venturi I4. I6 is ahollow choke operating shaft which is mounted on a stationary hollow shaft 60. I! is one of two tongues (Fig. 3) extending from the hollow shaft I6 and engaging a corresponding slot I9 in one-half of the choke valve I2. This choke valve I2 is made of two similar stampings which together form a cylinder embracing the stationary shaft 60. The two halves may be spot welded together. An opening is provided in the center of the choke valve I2 and a disc 64, held to the shaft 60 by a cap screw 66, closes this opening when the choke valve I2 is closed as shown in Fig. 2. A radial opening 6|, in the shaft 60, and a corresponding slot in the plate 64 provides an opening for fuel to discharge into the throat of the venturi I4. An inclined passage 62 connects the (o1. sci- 62) hollow shaft and radial opening B-I with th'e well 50 which is fed from a 'constant level fuel supply chamber 4'6 where the l'evel is maintained constant at the line 4 A-restr'iction'48 controls the fuelfiair ratio. "-A'n impact air -tube*52admits air *to'th'e wen-so through th'etub'e 54. A low -=speed fiiel bypass 56 is air bled'-at"58 to prevent a syphon actioh; Two outlets "=4'2'and 44 are sprovided so that as the throttledfi is first op ened fuel is' drawn'upbypass "55 and down passage "40- in a well known.

The throttle3'8is mcuntedbn a shaftfl driven by-lever4l. The choke=shaft I-6is driven by leve'r 22.

Similar numbers refer to similar parts-in Fig s. 4-and 460 is the stationary nozzle corresponding -to the nozzle Bilof Fig. 1'. 4152 is the" choke valve. Integral with the nozzle "I69 is the mircular fl nge J64 in the middle of which-is an opening HSI through "which the f uel discharges. The choke valve I I2, as 'befora -is rnade of two similar parts embracing the nozzle I60. In order that the flange I64 can be assembled a new part III has been added as a bushing surrounding the hollow driving shaft I6. The left hand face of the bushing III is machined to conform with the shape of the venturi I4. The diameter of the bushing I0 is the same as the diameter of the flange I64. A slot H9 now extends the full distance from the outer periphery to the inner annular opening I I I, otherwise it would not be possible to assemble the choke valve IIZ onto the stationary nozzle I60. A shallow opening I14 is provided in the downstream face of the stationary nozzle I66 and it is located so that the concentric opening I6i is concentric with reference to the opening I74.

Operation Assume the choke is closed as shown in Fig. 2 then the fuel is drawn up the well 50, down passages 6| and 62 into the venturi I4 where it mingles with the air which leaks around the disc 64 and choke valve I2. When the choke valve I2 is wide open the disc 64 serves to create an eddy into which the fuel is sprayed from the hollow stationary shaft 60.

The fuel is thus spread in a fan over the annular choke valve which serves to distribute the fuel uniformly in the air stream.

The operation of the carburetor shown in Figs. 4, 5, 6, '7, and 8 is substantially identical with that shown in Figs. 1, 2 and 3 with this exception;

The nozzle I6] is now concentric with reference to the venturi 14 whereas before it was necessarily located eccentric in order to clear the cap screw 66.

What I claim is:

1. A carburetor having a Venturi mixing cham ber, a mixture outlet and a throttle valve therein, a first hollow shaft mounted in a fixed position transversely in the throat of said venturi, a second hollow shaft concentrically mounted on said first shaft, a butterfly choke valve having two radial cylindrical portions rotatably mounted on the first shaft, driving means on said second shaft,

corresponding driven means on said choke valve, a constant level fuel supply chamber connected to the center passage of said first shaft, a radial opening in the first hollow shaft discharging downstream into the venturi, an opening in the center of said butterfly choke valve so that the fuel is discharged into the center of the Venturi in all positions of the choke valve.

2. A device as set forth in claim 1 in which there is a disc mounted on the stationary shaft in a horizontal position so as to intercept the opening through the first hollow shaft and so located as to close the .air opening in the center of said choke valve when the choke valve is closed without obstructing the flow of fuel.

3. A choke valve and fuel nozzle construction comprising an air passage, a fuel nozzle projecting at right angles into the air stream, an annular butterfly choke valve rotatably mounted on the nozzle said nozzle terminating in an opening in the middle of the air stream facing down stream, and a stationary disc mounted on the nozzle immediately upstream of the fuel outlet from said nozzle.

4. A choke and fuel nozzle construction comprising a Venturi mixing passage, a fuel nozzle projecting at right angles to the air stream into the throat of said venturi, a two part flat annular choke valve embracing said nozzle so as to rotate thereon, a radial opening in said nozzle discharging downstream inside the annular opening in said choke valve equally distributed on the upper inside edge of the downstream half of said valve, a disc carried by said nozzle upstream of said discharge point so as to fit into the opening of the annulus when the choke valve is closed.

5. A choke and nozzle construction comprising a Venturi mixing passage, a stationary fuel nozzle projecting at right angles to the air stream into the throat of said venturi, a flat annular choke having a tubular radial portion adapted to fit over the nozzle, a hollow shaft mounted on an extension of the nozzle clear of the Venturi and engaging with said annular choke valve, a radial opening from said nozzle pointing downstream and located within the central opening of a disc carried by said nozzle immediately upstream of said opening.

6. A carburetor having an air entrance including an annular butterfly choke valve with. radial bearings, a one piece fuel nozzle discharging downstream into the center of the air stream and located at right angles thereto and having a disc normal to and in the center of the air flow made integral with the nozzle, said disc being located adjacent to and upstream of the point of discharge of said nozzle, said nozzle being made to act as the pivot for the bearings of the butterfly choke valve, the central opening of said annular choke valve being equal in diameter to the diameter of the said disc, and a mixture outlet and a throttle valve therein.

WILLIAM E; EGERER.

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

UNITED STATES PATENTS

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