US2529665A - Floatless carburetor - Google Patents

Description

Novo M 11950 A. c. RUSSELL 2,529,665

FLOATLESS CARBURETOR Filed May 12, 1947 INVENTOR.

Patented Nov. 14, 1950 UNITED STATES PATENT OFFICE FLOATLESS omnrms'ron Andrew Craig Russell, Shawnee, Okla. Application May 12, 1947, Serial No. 741,409.

1 Claim. ((1261-60) This invention relates to devices in the nature of a carburetor for internal combustion, engines and has for its primary aim the provision of a fuel mixing apparatus that is entirely automatic in its operation and devoid of the fuel chamber float present in common types of carburetors.

The most important object of this invention is to provide a carburetor similar in many respects to that disclosed in my previous issued U. S. Letters Patent No. 2,366,056, dated December 26, 1944, and to improve upon the carburetors shown in my co-pending applications Serial Numbers 646,767, 691,944 and 710,519, dated February 11, 1946, August 21, 1946 and November 18, 1946, respectively. This is a continuation in part of said applications.

Another important object of this invention is the provision of a carburetor having a fuel bowl provided with an inlet connected with a source of fuel supply and an overflow pipe for carrying excess fuel back to the source of supply to the end that a continuous flow is present when the carburetor is operating at less than full capacity.

A further object of this invention is to provide a carburetor having the aforesaid means for supplying fuel thereto and a valve assembly operable entirely by the extent of air flow through the carburetor.

A still further object of this invention is to provide a floatless carburetor for internal combustion engines having a tubular member interconnecting the carburetor housing and the fuel bowl and provided with a plurality of passages for introducing air from the interior of the housing to the level of'fuel within the tubular member.

Another object of this invention is to provide a carburetor of the aforementioned type having a collar within the housing in circumscribing screw-threaded engagement with the tubular member and .having a portion surrounding and in spaced relation to the outlet ends of the aforesaid passages, all to the end that air may enter the tubular member and mixing chamber therein at all times in an even, steady flow.

Many minor objects of this invention will be made clear or become apparent during the course of the following specification, reference being had to the accompanying drawing, wherein:

Fig. 1 is a vertical substantially central sectional view through a floatless carburetor made in accordance with my present invention; and

Fig. 2 is a cross sectional view taken on line 11-11 of Fig. 1, looking in the direction of the arrows.

A hollow housing broadly designated by the numeral III is sectional and when assembled, presents an air intake I2, and an air outlet [4 which is in communication with a pipe not shown, leading to the intake manifold of the internal combustion engine in the usual manner.

intake passage I2 is equipped with a butterfly valve It to control the carburetor.

A fuel bowl l8 forms a part of the housing II and depends from the normally lowermost wall 20 thereof. This fuel bowl l8 may be detachably secured to the housing Ill in any suitable manner to present a hermetically sealed chamber for receiving the fluid from a source of supply.

The fuel bowl I! may be drained if desired, by removing a plug 22 disposed in the normally lowermost wall of fuel bowl l8. An elongated tubular member 24 disposed within the fuel bowl I! passes through an opening formed in the wall 20 of housing l0 and tinuous air passage through housing 10 which interconnects intake l2 and air outlet l4. This tubular member 24 is provided with a pair of spaced apart substantially'parallel plates 26 and 23 for purposes hereinafter more fully described and the plate 26 underlies and is secured to the wall 20 through the medium of screws or the like, not shown. The normally uppermost end of this tubular member 24, or that portion thereof which extends into the housing It), is externally threaded as at 30 to receive an internally threaded collar 32. The threads 34 of this collar 32 are in mesh with the threads 39 of member 24 to the end that rotation of the collar 32 moves the lowermost end thereof toward and away from the innermost face of the bottom wall 20 of housing III.

This collar 32 is provided with a plurality of longitudinal ribs 36 and a screw 38 is threaded into a threaded bore 40 formed in one wall 42 of housing l0. This screw 33 extends into the housing l0 and is in contacting relationship with the collar 32 when the screw 38 is in the operative position. When the innermost end of screw 23 is in engagement with collar 32, the ribs 26 prevent rotation of collar 32 with respect to the tubular member 24. When the collar 32 is set in the desired position, a lock nut 44 on the screw 33 amount of air entering the extends upwardly into the con- 7 asaaoes and disposed exterlorly of housing Ill, holds screw 22 in the operative position.

A pair of spaced apart substantially parallel posts 44 are slidably mounted within openings 44, II and 42 in wall 2|, plate 24 and plate 28 respectively. A disc i4 disposed within the fuel bowl ll joins the lowermost ends of the posts 48 and the uppermost ends of these posts 40 are joined by a closure 54 mounted within the passageway through housing l joining intake l2 and outlet l4. This closure member It rests upon the collar 22 and cooperates therewith in substantially closing the passageway through housing in when the assembly, including posts 46, is at the lowermost end of its path of travel as illustrated in Figs. 1 and 2. A longitudinal bore 58 is formed within the member 24 and has press-fitted or otherwise afilxed thereto a pipe 60 at its normally uppermost end and this pipe 60 terminates within the housing III in spaced relation to the closure and the collar 32. The other end of the bore 58 has a tubular plug 62 threaded therein for slidably receiving a tapered valve 64. This valve 64 substantially closes the opening through the plug 82 when the plate 54 is at the lowermost end of its path of travel. The valve 64 rests upon the disc 54 joining the posts 46 and is actuated by the vertical reciprocating movement of posts 46, disc 54 and closure member 56.

The longitudinal bore 58 formed in the member 24 is of reduced diameter intermediate the ends thereof to present a restricted passage 66. A plurality of passages 68 extend downwardly and inwardly from housing ill to interconnect the latter with the terminate at their inner ends above, and in spaced relation to the passage 88, and above the level of fuel within the bowl l8 and within the bore 42. The passage 66 serves to maintain said level of fuel within bore 58 below the inner end of passages N.

The normally lowermost end of the collar 32 is providedwith a cavity ill of greater diameter than the threaded bore 34 thereof and this cavity III is in clrcumscribing spaced reationship to the normally uppermost and outermost ends of the passages 68, as clearly illustrated in Fig, 1 of the drawing.

The operation of the valve 64 is similar to that disclosed in my aforesaid U. S. Letters Patent. This constitutes essentially an opening and closing of the valve 64 by longitudinal reciprocation thereof within the bore 58 through actuation of the disc 54. As a greater or lesser amount of fuel mixture is allowed to pass into the internal combustion engine through the operation of the butterfly valve between the car-' buretor and the manifold as above described, air passing through the housing lo from inlet l2 into the air outlet l4, will raise and lower the member 58 from the collar 32, permitting such air to pass upwardly around collar 32 to mix with the mixture emanating from the uppermost end of the pipe 60. During operation of the internal combustion engine, air is free to flow into the bore ss through the passages 68 except during choking when the butterfly valve I6 is moved to a position to present a richer mixture.

As set forth in my U. S. Letters Patent No. 2,366,056, there is a level of fuel within the bore 5' below the innermost ends of the passages 68, and as air enters bore 58 it strikes the shoulder therein, produced by the reduced passage 66 thereof and creates a turbulence. This turbulent air acts upon the level of fuel in bore 58, and the interior of bore 58. These passages 68 mixture is moved toward the outlet end of pipe 44 by suction in the mine.

Collar 22 prevents a direct flow of air from the housing is into the bore 40, the passage being somewhat circuitous and, therefore, equalized pressure is attained before entrance of the air into bore 52;

It is through use of the assembly just described that it is possible to eliminate the usual type of float within the fuel bowl ll. In lieu thereof, this carburetor is provided with an inlet opening 12 for receiving a conduit 14 having connection with the usual type of fuel pump not shown, which receives fuel from a source of suply in the usual manner. A fitting It communicating with the fuel bowl is below the intake opening 12 has connection with an overflow pipe 18. This overflow pipe has the opposite end thereof connected to the conduit which joins the fuel pump of the internal combustion engine with the fuel tank. when the engine is idling and the fuel pump is operating, a continuous flow of fuel passes from the fuel pump through the conduit I4 into the opening 12 and finally into the fuel bowl is. The carburetor, during such idling operation of the engine, uses only a small amount of the full capacity of the fuel pump and the conduit 14 and such excess overflows into the pipe 18 and empties back into the pipe interconnecting the fuel pump and the fuel tank. As the amount of fuel being used by the internal combustion engine is increased through the operation of the carburetor just above described. the extent of overflow of fuel into the pipe 18 progressively decreases. Obviously, the total capacity of the conduit 14 is greater than the total capacity of the overflow pipe 18 and by the same token, when the carburetor is operating at full capacity, the capacity of the conduit 14 is such as to maintain a level of fuel in bowl is substantially as shown in Figs. 1 and 2. In other words, as the greatest amount of fuel which may pass through the bore 58 of member 24 is reached, the extent of overflow of fuel from the pipe 18, decreases. It is seen, therefore, that during operation of the carburetor, the fuel bowl I! always contains enough fuel to supply bore 58, 68 and as the valve 64 is moved toward the closed position, an increasing amount of fuel will overflow into the pipe 18. Thus the level of fuel in bowl [8 will vary slightly during operation, particularly during rapid acceleration changes, but will never raise or drop to a great extent with respect to overflow pipe 1!.

Formation of the carburetor as just described, eliminates many unnecessary parts which decreases the cost of production substantially and provides for a more efficient operating carburetor generally.

The elimination of means for actuating the collar 22 as provided in my aforesaid U. S. Letters Patent, as *well as omission of the float within the fuel bowl l8, obviates the need of a multitude of parts that would otherwise tend to cause trouble because of maladjustment and other operating defects. Furthermore, it has been found that the carburetor as herein disclosed, operates as efficiently with these parts eliminated and has the same advantages with respect to economy and excellence of performance as the carburetor forming the subject matter of my aforesaid patent. In addition, the improvements herein set forth increases economy of operation, decreases initial cost of production of the carburetor and enhancessmooth operation.

I the fuel bowl and extending into the housing through said one wall thereof, said tubular member having a mixing chamber formed therein and a plurality of passages disposed to direct air from the housing into said mixing chamber and thence downwardly against the surface of fuel therein, the improvement of which includes a collar having an outturned flange at the upper end thereof and a plurality of grooves formed on the periphery of the collar below said fiange,said

grooves being parallel to the axis of rotation of the collar, a portion of the collar being in circumscribing relationship with the tubular member adjacent the outermost ends of said passages and spaced therefrom; a movable annular valve in the passage and resting on said flange when at one end of its path of travel; a second valve operably joined to the first valve for controlling the flow of fuel from the bowl to the mixing chamber, said collar being threadably mounted on the tubular member for adjusting the position of the valves at said one end of the path of travel; and a set screw threadably mounted in the housing for engagement with said grooves whereby said collar is releasably held from movement out of adjustment.

ANDREW CRAIG RUSSELL.

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

UNITED STATES PATENTS Number Name Date 1,333,982 Jensen Mar. 16, 1920 1,783,273 Beach Dec. 2, 1930 2,271,113 Bracke Jan. 27, 1942 2,366,056 Russell Dec. 26, 1944

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