US2038206A - Carburetor - Google Patents

Description

Patented Apr. 21, 1936 UNITED STATES PATENT OFFICE Claims. (Cl. 26134) This invention relates to carburetors, and more particularly to an economizing device for con.- trolling the flowof fuel to the fuel nozzle of a carburetor.

An object of the invention is to provide an economizer which is simple to construct and easily assembled in place;

Another object of the invention is to provide an economiz'er which is positive and dependable in operation.

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

Figure 1 is a vertical section through the float reservoir ofa carburetor embodying the inventlon;

Figure 2 is a fragmentary vertical section showing a modified form of the invention; and

Figure 3 is an enlarged sectional view taken on the line 3--3 of Figure 1, showing the upper economizerunit.

Referring more particularly to Figure 1., the

carburetor shown is of the up draft type, although" it will be understood that the invention may be as readily applied .to other types of carburetors. The body of the carburetor, indicated generally at 10, forms a vertical air passage which is controlled by a throttle I2 and has mounted therein a venturi l3 and fuel feeding mechanism of any suitable type (not shown) A float reservoir I4 is provided with the usual float and associated mechanism (not shown) for controlling the level of fuel therein; and has mounted therein an acceleration pump comprising an inverted cup 5 actuated ,upon movement of the throttle through a rod I8, and having therein a spring pressed piston 2|] slidable on a stud 22 having a bore 24 communicating at its upper end with the interionof the cup l6 and at its lower end with a bore 26. 'A transverse bore 28 communicates with the bore 26 and leads therefrom to the main noz'zle. Float reservoir I4 is completely closed at its top by a detachable cover 29 integral with the body ill of the carburetor. Cover 29 has an integral, upwardly-projecting boss 3| for the accommodation of the economizer valve-actuating mechanism, as'will be hereinafter more particu-- larly described. Other features of the carburetor are more fully described and. claimed in my 00- pending application, Serial No. 566,934, filed October 5, 1931, now Patent 2,015,709 issued October, 1935. i

The economizer is also located within the float reservoir, and comprises a plug 32 threaded into plunger.

thevbottom of the float reservoir and-having a transverse duct 34 which communicates through avertical passage with a horizontal duct which connects with the bore 28. The vertical passage is controlled by a valve member 36 having; avertical stem projecting above the plug 32 and, urged upwardly by a compression spring 38 which is held in position by a stamped cup 40 frictionally seated in the ..vertical duct and provided with a metering orifice42 therein.

A cylindrical chamber 43 is formed in boss 3| on cover 29 directly above the plug 32 and communicates by means of a duct 44 with the main air passage of the carburetor posterior to the throttle. A piston 46 is reciprocably mounted in chamber 43 to be actuated by the suction through duct 44 and has secured thereto a plunger 48 which is loosely and slidably mounted in a plug 50 and urged downwardly by a compression spring 52: engaging a collar at the lower end of the Piston 46 is formed with a depending sleeve, as shown in Figure 1, and has a socket which receives the upper end of plunger 48 in loose-fitting relation. Av pin 41 secures the plunger to the piston and-rests in an elongated slot in the plunger so as to form a universal con-. nection between the plunger and piston which permits the piston to reciprocate without binding even if plug 50 is out of alinement with piston 45. A transverse slot 49 is formed in the upper surface of the piston to permit air pressure acting through duct 44 to be exerted over the entire upper surface of the piston. An annular groove 5| is formed in the piston, since such groove has been found by experiment to produce a damping action preventing vibration of the piston.

A vent ,54 opens from chamber 43 to a passage 53 formed between the venturi l3 and the wall of the main air passage, asshown in Figure 2. Passage 53 communicates with the air horn of the carburetor by one or more slots 55 formed in the supporting flange of the venturi. The other end of passage 54 lies adjacent a series of notches 56 formed in the upper portion of a plug 50 so that when piston 46 is in its lowermost position atmospheric pressure may still act upon its under surface to raise it against force of spring 52.

In the modification illustrated in Figure 2, the parts are the same except as hereinafter noted.

' Instead of the valve 36 a ball valve 58 is mounted in the plug 59. The ball valve is urged upwardly by means of a spring .60, and may be moved downwardly by a stem '62. A metering plug 64 is threaded or frictionally held within the vertical bore of the plug. The bore 43 communicates by aport it with themainairpassageofthe carburetorinthesamemannerasinllgures l and 3, and the piston "is formed of a flanged metallic member, within which is seated a helical spring III, with a leather washer ll covering the piston to form an air-tight connection. A down wardly extending flange 12, formed on the piston,

is pressed into a corresponding groove in the plunger ll to secure the, piston in place.

In both embodiments it will be noted tintthe economizer comprises relatively few parts and that the upper and lower units thereof may each be completely assembled before being inserted in the carburetor.

While the invention has been described with reference to certain speciflc embodiments thereof, it will be understood that the invention is not limited to these embodiments, or otherwise, except by the terms of the following claims.

I claim:

1. In a carburetor, an economize: comprising a chamber-subjected to varying air pressures and having a port communicating with an air passage of the carburetor, a piston reciprocable in the chamber and having an annular groove in its periphery intermediate its ends, a plunger 1miversally connected to the piston, and means actuatd by the plunger for controlling the flow of fuel in the carburetor. v

a 2. In a carburetor having a float reservoir providedwlth a cover, an economizer for restricting the flow of liquid fuel from said reservoir, comprising a valve unit attached to the bottom of said reservoir, and a valve-actuating unit held vby said cover in operative position with respect to said valve. each of said units being so constructed as to permit them tobe completely as M sembled before being attached to said reservoir and cover respectively. 3.1nacarburetorhavingamainairpassage controlled by a throttle, a float reservoir provided with a cover, an economizer for restricting 5 the flow of liquid fuel from said reservoir, comprising a cylindrical chamber formed in said v cover and communicating with said passage posterior to said throttle, a piston in said chamber, a portleadingfrom'saidchambertosaidpassage o anterior to said throttle, and means for limiting said plug for limiting movement of said piston toward said plug.

5. Ina carburetorhavingamainairpassage controlled by a throttle, a float reservoir provided with a cover, an economizer for restricting the flow of liquid fuel from said reservoir, comprising a cylindrical chamber formed in said cover and 80 communica with said e posterior to said throttle, a piston in said chamber, and a plunger depending from said chamber in said reservoir and having a universal connection with said piston. I as JIIL'I'ON E. CHANDLER.

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