US2043514A - Carburetor - Google Patents

Description

June 9, 1936. M. MENNESSON CARBURETOR Filed Nov. 20, 195s 5 Sheets-Sheet 1 uwgwrae R m m 4 Z a a 6 June 9, 1936. MENNE -N 2,043,514

' CARBURETOR Filed Nov 20, 192; 5 Sheets-$heet '2 uwE/v Torr Mg ce/ Men/765500 A T ENE TS June 9, 1936. MENNESSON v 2,043,514

CARBURETOR Filed NOV. 20, 1955 5 Sheets-Sheet 3 INVE/V T0 @a rce/ Men/765600 4 TTOIP VE Y8 Patented June 9, [936 UNITED STATES PATENT OFFICE CARBURETOR- Application November 20, 1933, Serial No. 698,897 In Belgium November 25, 1932 8 Claims.

The present invention relates to carburetors for internal combustion engines. Itsobject is to provide a device for facilitating the starting of an internal combustion engine and its running when cold.

It has become usual to obtain the starting of an internal combustion engine and its running when cold by means of an auxiliary carburetor which is substituted, during these periods, for the chief carburetor. This auxiliary carburetor is adjusted independently from the chief carburetor in such manner as to satisfy the particular, and very variable, conditions that are met with during these periods. As the gaseous mixture should be the richer in fuel as the engine is colder, and as, on the other hand, the speed of revolution of the engine during these periods depends on the internal resistances created by the state of viscosity of the lubricating oil (which resistances are the greater as the engine is colder) the auxiliary carburetor should be provided with means for causing it to supply a mixture in which the percentage of fuel decreases as the speed of revolution of the engine increases. Such a device is described in the patent to Goudard, No. 1,958,818, issued May 15, 1934.

These means are generally adjusted in such manner as to satisfy ordinary average conditions. But it may occur that these average conditions are exceeded and that the temperature becomes so low that when the engine is starting and beginning to run, before it reaches the average conditions above referred to, it would be advantageous to increase the richness in fuel of the mixture still more than for these average con ditions of starting. In other words, at a temperature lower than the average temperature of start ing, the engine may be caused to start and to run, either at the same speed of revolution as for these average or normal conditions, or at the lowest speed at which it can run without stalling, if the percentage of fuel in the mixture is further increased. However the fuel mixtures that correspond to these extreme conditions are not suitable for the average, or normal, conditions of starting and it is useful to maintain means for supplying a fuel mixture corresponding to these normal conditions. It is therefore necessary to employ, when these extreme conditions occur, either auxiliary means for completing, replacing, or transforming the auxiliary carburetor that ensures starting under normal, or average, conditions.

According to the present invention, in a carbureting system including an auxiliary carburetor adapted to feed the engine with the appropriate fuel mixture for starting under normal, or average, conditions, I provide an auxiliary device adapted either to supplement, replace, or transform this auxiliary carburetor when it is desired to increase the percentage of fuel in the mixture so as to meet the requirements of extreme conditions.

Other details of my invention will appear from the following detailed description thereof.

Preferred embodiments of the present invention will be hereinafter described, with reference to the accompanying drawing, given merely by way of example, and in which:

Fig. l is a vertical diagrammatic sectional view of the device according to the present invention;

Figs. 2 and 3 show respectively, in two different characteristic positions, another embodiment of the device according to the present invention;

Figs. 4 and 5 are axial vertical sections of another embodiment of the device according to the present invention, in two different characteristic positions;

Fig. 6 is a vertical sectional view of a modification of the embodiment shown in Figs. 4 and 5;

Fig. 7 is a sectional view of still another embodiment;

Figs. 8 and 9 are sectional views of two other embodiments.

As shown in Fig. l, the main carburetor comprises a float chamber I, jets 2 and 3, a slow running passage 4 and a suction pipe 5 provided with a throttle valve 6.

The auxiliary carburetor comprises a passage 1 connected to float chamber l this passage feeding a flooded calibrated orifice 8 located at the lower part of a well 9 open to the atmosphere. An uptake tube I0, dipping in said well 9, discharges fuel at H into the inlet l2 of a mixture passage i3 provided with a valve [4 and opening at l5 into the suction pipe 5 beyond throttle valve 6.

According to my invention, I provide in the wall of passage 1 a second calibrated orifice I6 through which fuel can be fed to the lower end of a well I! in which is located an uptake tube Hi. This tube 18 feeds fuel, at [9, into the inlet 20 of a second mixture passage 2| provided with a valve 22. This passage 2| may either, as shown in Fig. 1, open directly into suction pipe 5, or, as shown in Figs. 2 and 3, open into the first mixture passage !3 beyond the valve 14 thereof, so that, in the latter case, passage 2| communicates with suction pipe 5 through a common outlet [5.

It is clear that the working of this supplementary carbureting device is quite similar to that of the auxiliary carburetor, the rate of flow of the fuel being independent of the velocity of the air sucked in through the mixture passage so that the percentage of fuel in the mixture that is formed decreases as the speed of revolution of the engine increases. This supplementary carbureting device is a fraction of the auxiliary carburetor the operation of which can be controlled independently and limited to such periods as those in which it may be useful.

To this efiect, the means for controlling the auxiliary carburetor and the supplementary carbureting device may be conjugated. For instance the control rod 23 of the lever 24 of valve 22 is connected to the lever 26 of valve l4 through resilient means, for instance a spiral spring 25 interposed between lever 24 and lever 26. A stop 21 limits the movement of lever 25 to the position for which valve 14 is open. Once this position has been reached lever 24 is still allowed to turn through a certain angle, by stretching spring 25, until valve 22 is fully opened, an abutment 28 stopping said lever 24 in this position.

When the driver actuates control rod 23 both of these levers 24 and 26 are caused to rotate, but valve 22 is still closed when valve it opens. As lever 26 is stopped in the position that corresponds to said valve 14 being open, lever 25 opposes a further rotation of lever 24. If however the driver acts more strongly on control rod 23, the resistance of lever 25 can be overcome and lever 24 is eventually brought into contact with stop 28, for which position valve 22 is open. The supplementary carbureting means are thus brought into play, which permits of feeding a supplement of fuel to the suction pipe. If the driver then releases control rod 23, spring 25 returns lever 24 into the position shown in Figs. 1 and 2, for which valve 22 is closed, while valve l remains open. The auxiliary carburetor 8- I0l3 is then left to work alone, while the auxiliary carbureting means i6l8--2i are put out of operation. To bring both of these carbureting devices out of operation, it suffices to actuate control rod 23 toward the right hand side of the figure so that lever 26 is moved away from abutment 21, thus closing valve M. As for valve 22 it is necessarily closed before valve M.

The embodiment of Figs. 2 and 3 is wholly similar to that of Fig. 1, with the exception that, in this case both passages I3 and 2| have a common outlet l5 into suction pipe 5.

Figs. 4 and 5 show another embodiment of my invention which differs from those above described in that a single valve 29 controls both the auxiliary carburetor and the supplementary carbureting means. In this case, the control rod 23 is connected with a lever 3i operatively connected with said valve 29. A stop 32 carried by a rod 34 slidable in a stationary support 35 is subjected to the action of a spring 33. Under the action of control rod 23 is brought into contact with said stop 32 (Fig. 4), without compressing spring 33. This corresponds to valve 29 fully connecting passage i3 with the uptake tube it] of the auxiliary carburetor. If control rod 23 is subjected to a supplementary eflort, spring 33 is compressed (Fig. 5), thus permitting valve 29 to turn into a position for which the uptake tube E8 of the supplementary carbureting means is placed in communication with passage l3.

I will now describe embodiments of my invention in which the supplementary carbureting means are capable of delivering the whole of the amount of fuel that corresponds to extreme conditions of starting and running. In this case I provide means for substituting this supplementary carbureting device for the auxiliary carburetor, which is then brought out or" action when said supplementary carbureting device is brought into play To this effect, it suifices, as shown for instance in Fig. 6, to arrange valve 29 and the width of its aperture in such a way that it opens the connection between uptake tube 98 and passage 53 only after having closed the communication between uptake tube Ill and passage 53.

In the embodiment shown in Fig. '7, the jet Iii-H of the auxiliary carburetor is disposed in the wall I! of the supplementary carbureting device, for instance in parallel relation to the jet |8-l9 thereof. The uptake tube it has its lower end at a distance below the level in float chamber I that corresponds to the desired conditions of working of said uptake tube it. The section of calibrated orifice I 6 is chosen to correspond to the maximum total feed. If only jet H is in operation, due to valve 23 connecting it with passage I3, the partial head of the fuel in the float chamber will correspond to height h and the feed through orifice 18 will be a function of this head. If now valve 29 brings passage 29 into communication with passage l3, the fuel flowing through jet l9 absorbs the contents of well ll thus stopping the flow through jet I I and causin the feed through orifice It to correspond to the height H between the level in the float chamber and the lower end of tube I8.

I may also, as shown in 8, superpose the auxiliary carbureting means and the supplementary carbureting means. In this case, tube It! is merely the upper portion of tube it, applied against it by a spring 38 interposed between a disk 31 rigidly fixed to said tube I3 and a collar 39 integral with the outer face of well ll. When tube It] is not applied against tube i8 it only absorbs, as above explained with reference to Fig. 7, a feed corresponding to head h. On the contrary, when an arm 36 of lever 53! applies the lower end of tube l3 against the upper edge of tube I 8, against the action of spring tube it becomes merely an extension of tube 58, and the feed now corresponds to head H.

Finally, as shown in Fig. 9, I may make use of a single uptake tube It], placed in a well 9 which communicates with feed passage 1 through. two diiierent orifices 8 and I6. Orifice i3 is controlled by means of a needle 48 urged in a downward direction by a return spring Gil and adapted to be moved upwardly by an arm ll of lever 3| when the latter is compressing spring It will be noted that, with the arrangements above described, the driver needs not take especial care of the controlling of the supplementary carbureting means. It will be through a kind of refiex action caused by the difiiculty of starting that he will exert a still greater pull on control rod 23 so as to deform spring 25 or 33 and thus bring into play the supplementary carbureting means.

While I have described what I deem to be prac tical and efiicient embodiments of the present invention, it should be well understood that I do not wish to be limited thereto as there might be changes made in the arrangement, disposition and form of the parts, without departing from the principle of my invention as comprehended within the scope of the appended claims.

What I claim is:

'1. An engine carburetor including a throttle, a main mixing chamber, :means for supplying mix-- ture to the engine :for normal running when the associated engine is hot, a'first auxiliary mixing chamber for supplying mixture to the motor under mean average conditions while cold and opening at one end to the atmosphere and at the other end to said main mixing chamber on the engine side of said throttle, a first independent jet for feeding carburant to said auxiliary mixing chamber under mean average conditions of the motor while cold, a second auxiliary chamber open to the atmosphere, a second independent jet for supplying auxiliary mixture to this second chamber when said mean average conditions are exceeded, a valve for stopping the flow of mixture from said first independent mixing chamber to the main mixing chamber, means to control this valve, said valve further having a passage therein for controlling the flow of mixture from said second auxiliary mixing chamber to said first auxiliary chamber.

2. In a carburetor according to claim 1, an elastic stop to arrest the movement of said control means, said valve controlling the auxiliary mixing chambers in such a manner that in one position the first auxiliary mixing chamber is ennpletely open and in a second position the second auxiliary mixing chamber is completely open.

3. An engine carburetor including a throttle, a main mixing chamber, means to feed mixture to the engine for normal running when the engine is hot, auxiliary means to feed a richer mixture to the engine under mean average conditions while cold, independent auxiliary means to feed a still richer mixture to the engine when said mean average conditions are exceeded, both said auxiliary means being connected with said main mixing chamber on the motor side of the throttle, a valve to control the flow from said two auxiliary means to the main mixing chamber, said valve operating first to connect the first auxiliary means to the main mixing chamber and then to connect both auxiliary means to the main mixing chamber, means to control the movement of the valve, and an elastic stop to maintain said valve in the position which corresponds to that in which the first auxiliary means only is connected to the main mixing chamber.

4. An engine carburetor comprising a throttle, a main mixing chamber, means to feed mixture to the engine for normal running when the associated engine is hot, auxiliary means to feed a richer mixture to the engine under mean average conditions while. cold, independent auxiliary means to feed a still richer mixture to the engine when said mean average conditions are exceeded, both said auxiliary means being connected to the main mixing chamber on the engine side of the throttle, a valve for controlling the connection of one of said auxiliary means to the main mixing chamber, means to control the movement of the valve, and an elastic stopfor holding said valve in the position which corresponds to the connection of the first auxiliary means with the main mixing chamber.

5. An engine carburetor comprising a throttle, a main mixing chamber, means to feed mixture to the engine for normal running when the associated engine is hot, said means being connected to the. main mixing chamber on the engine side of the throttle, a float chamber, a conduit connecting said float chamber with said means, a vertical well, connected by a calibrated orifice with said conduit, two tubes of unequal length extending into said well,-carbureting means arrangedat the upper ends :of said tubes, means for connecting both said carbureting means to the main mixing chamber, a valve forcontrolling said connectingmeans, said valve in one position connecting the carbureting means at the upper end of the shorter tube only to the main mixing chamber, and in another position connecting both carbureting means to the main mixing chamber, means to control the movement of the valve, and an elastic stop tending to maintain the valve in the position in which only the carbureting means at the upper end of the shorter tube are joined to the main mixing chamber.

6. An engine carburetor comprising a throttle, a main mixing chamber, means to feed mixture to the engine for normal running when the associated engine is hot, said means being connected tothe main mixing chamber on the engine side of the throttle, a float chamber, a conduit connecting said float chamber to said means, a vertical well connected by a calibrated orifice with said conduit, two tubes arranged in said well coaxially one above the other, in such a manner that the lower extremity of the upper tube can rest against the upper edge of the lower tube, elastic means urging said tubes apart, carbureting means disposed at the top of the upper tube and connected with said mixing chamber beyond said throttle, a valve to control communication between the carbureting means and the mixing chamber, means to control the movement of this valve to open the valve first and then simultaneously to leave the valve open and to move the tubes into contact with each other, and an elastic stop tending to hold the control means in the position in which the valve is opened and in which the tubes are held apart from one another.

'7. An engine carburetor including a main jet and a main mixing chamber for normal running, a slow speed jet and an auxiliary mixing chamber for slow running, a throttle simultaneously controlling said main and said auxiliary mixing chambers for supplying mixture to the. engine when said engine is hot, in combination with an auxiliary carburetor assembly comprising an independent mixing chamber for supplying mixture to the engine while cold and opening at the engine side of said throttle, an independent jet for feeding fuel to said independent mixing chamber under mean average conditions while cold, means open to the atmosphere for supplying carburant to said independenet jet, means for restricting the supply of fuel to said jet so that the mixture in said independent mixing chamber is progressively impoverished with increase of the suction, air inlet means for said independent mixing chamber, auxiliary means associated with said independent jet and independent of said air inlet means for the supply of fuel to said independent mixing chamber when said mean average conditions are exceeded and a valve. for controlling the flow of mixture from said independent mixing chamber to said engine.

8. An engine carburetor including a main jet and a main mixing chamber for normal running, a slow speed jet and an auxiliary mixing chamber for slow running, a throttle simultaneously controlling said main and said auxiliary mixing chambers for supplying mixture to the engine when said engine is hot, in combination with an auxiliary carburetor assembly comprising an independent mixing chamber for supplying mixture to the engine while cold and opening at the engine side of said throttle, an independent jet for feeding fuel to said independent mixing chamber under mean average conditions while cold, air inlet means for said independent mixing chamber, auxiliary means associated with said independent jet and independent of said air inlet means for the supply of fuel to said independent mixing chamber when said mean average conditions are exceeded and a valve for controlling the flow of mixture from said independent mix ing chamber to said engine.

MARCEL MENNESSON.

Images