US1731135A - Carburetor - Google Patents

Description

H. HUTCHISON Oct 8, 1928.

CAR'BURETOR Filed Feb. 19, 1926 2 Sheets-Sheet 2 .Ziz-tfanfur I I J1m Patented Oct. 8, 1929 UNITED STATES PATENT OFFICE CARBURETOR Application filed February 19, 1926, Serial No. 89,440, and in Great Britain June 9, 1925.

This invention relates to improvements in spray carburetors for internal combustion engines.

The object of this invention is to provide a carburetor by which the fuel is picked up as it issues through the nozzle and is finely atomized and diffused throughout the air, producing a mixture that is extremely intimate and forms a highly combustible vapour. To this end two supplies of air are caused to rotate, the one supply in one direction and the other in the opposite direction and the means for causing this are so arranged in relation to a mixing chamber that a main supply of air picks up, atomizes and diifusesthe fuel as aforesaid and this mixture as it issues from the mixing'c'hamber meets the other or supplementary supply of air rotating in the opposite direction which impinging on the mixture, breaks up and finely atomizes any particles of fuel in the vaporous mixture and at the same time causes the velocity of the mixture to be reduced.

A further object is to provide certain means to control or modify the action of the carburetor.

According to this invention, therefore, the carburetor has a mixing chamber around the fuel nozzle, an inner deflector extending across the whole space between the fuel nozzle and mixing chamber so as to rotate the main air current passing to the fuel nozzle and thereby bring it into intimate contact with the fuel drawn into the mixing chamber by the action of the engine, and an outer deflector for supplemental air on the outside of the mixing chamber arranged to cause this supplemental air to rotate and then mix with the combustible mixture issuing from the mixing chamber, the two deflectors being so arranged that the main and supplemental air currents rotate in opposite directions.

The air is preferably caused to rotate by means of fiat blades which are disposed at an arranged to overlap so that there is no straight passage for the air through the carburetor but all the air must rotate.

The fine atomization and intimate'mixture angle to the passage of the air and are also of air and fuel ensure the best possible conditions for perfect combustion.

An auxiliary or pilot nozzle for slow running is preferably provided in connection with the carburetor.

In one practical form the carburetor has a fuel nozzle, a tube above said nozzle being preferably provided with external vanes or distance pieces adapted to locate the tube within the carburetor in a position in which it is spaced apart from the walls thereof, blades constituting a deflector arranged to extend across the whole width of the mixing chamber slightly below the outlet of the fuel nozzle and acting to rotate the air which passes into contact with the fuel drawn into the mixing chamber by the action of the engine and outer blades extending across the whole width of the space between the tube and the wallof thecarburetor adapted to rotate the supplementary air which passes along the annular space at the outside of the tube. The blades of each deflector overlap each other, so that there is no straight passage through or around the mixing chamber while the blades of the inner deflector are arranged to rotate the main air in one direction and the blades of the outer deflector to rotate the supplementary air in the opposite direction. The inner and outer streams may be arranged to pass through a Ventuyi passage above the mixing chamber.

In order that the invention may be clearly understood and more readily carried into practice I have appended hereunto the ac-' companying drawings which show, by way of example, a mode of making the carburetor.

Fig. 1 is a sectional plan view of the carburetor.

Fig. 2 is a sectional elevation on line 2-2 in Fig. 1.

mixing chamber 2 fitted externally with dis tance pieces 3 to keep it in a central position.

The fuel nozzle 4 projects upwardly into the mixing chamber which is provided with a deflector consisting of a series of angularly disposed blades 5 surrounding the nozzle at a I justable Venturi choke 9 is also provided in the carburetor body adjacent the top of the mixing chamber, this choke being slidable within the body and having a screw 10 mounted in an elongated hole 11 and serving to limit the movement of the choke and also secure it in its adjusted position. In this manner air from the intake 12 can pass upwardly around the mixing chamber and the volume of air passing can be controlled'by the choke. The tapering top- 6 may also be provided with slots or openings 13, preferably obliquely arranged as shown but these openings may be of any suitable form.

The mixing tube is secured in position by means of a plate 14 attached to the carburetor body by means of a screw 15 and having a lug 16. provided with a slot 17 so as to engage with one of the pieces 3.

The auxiliary or pilot nozzle for slow running is provided with a tube 20 fitting snugly within the vertical bore 21 and having screwed in its lower end a nozzle 22. This nozzle is disposed with-its lower end just belowthe' fuel level- A deflector consisting of angle vanes 23 similar to those of the main nozzle are also provided just beneath the outlet opening of the nozzle 22. The air for the pilot nozzle passes through the inclined ports 24 which are situated above the normal fuel level and below the deflector, as shown in Fig. 3. The outlet is at 4:1.

The fuel for the main nozzle passes through the ports 2526 while thatfor the slow running nozzle passes through the port 25 as shown in Figs. 1 and 2 these ports con1- municating with wells 27 beneath the nozzles and these wells being provided with removable plugs 28 to p'rovide'ac'ccss to the nozzles when cleaning or replacement is necessary. In the construction illustrated the fuel passes to the ports froi-n a float chamber and this fioat chamber may be made integral with the carburetor or separately therefrom and in the latter case it will be detachably attached to the carburetor. Instead of a float chamber, a needle valve which can be manually controlled, as shown in. Fig. 5, may be used and this may be secured "inaa suitable position underneath the carburetor. This cock is provided with aninlet pipe 30 communicating with a tapered opening 31 in a plug 32 rotatably mounted in the cock and while in conjunction with this I may provide another throttle valve 37 arranged in the carburetor intake and connected by the extending arms 38-39 shown in Fig. 6, so as to act in unison. The throttle valve 37 in the carburetor intake is provided with ports 41 and through which a certain amount of air will pass when the throttle is closed and the arm is provided with a series of holes 42 any oneof whichcan be connected with the link 3 4:0 to provide for the adjustment of the position of the throttle valve 37 relatively to the throttle valve 36. The throttle valve or valves, where two are provided, are oper-' ated from any convenient position as, for ex.-

ample, from the dash board 01 a motor car or from the starting platform of a land or marine Diesel engine.

In action the air enters the intake under the control of the throttle valve 37 and 'di-. 1

vides into two streams one of which passes into the mixing chamber and is rotated in a particular direction by the blades 5. This rotary air comes into contact with the fuel drawn into the carburetor by the action of the engine and produces a combustible mixture which passes upwardly and issues from the top of the mixing tube. The other stream of air passes upwardly between the mixin tube and carburetor body and is prevente from passing directly through the carburetor by the blades 8 which rotate the air in an opposite direction to that of the central stream. The second stream comes into contact with the combustible mixture at the top of the'mixing chamber and the two streams impinge on one another as aforesaid.

Having now fully described my invention what I claim and desire to secure by Letters Patent is In combination, a carburetor body, a fuel primary air through its interior and a passage of constant size forv supplemental air around its exterior, said chamber having 1ts lower edge only slightly below the tip of said nozzle and having its major portion projectmg upwardly above said nozzle, vanes extending radially from the tip of the nozzle to the adjacent lower end of said mixing chamber which vanes are adapted to cause all primary air passing into said chamber to SWll'l in one direction, and prevent any of it from passing vertically therethrough, and

flat, inclined discontinuous vanes extending completely across the space between'the cylindrical mixing chamber and the cylindrical part of the body adapted to cause all supplemental air passing through said space to swirl in a. direction opposite to the primary air whereby the supplemental air impinges on the mixture issuing from said chamber so as to check the swirling motion thereof and leave a motionless gaseous mixture.

In testimony whereof I aflix m signature HUGH HUT HISON.

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