US2526673A - Carburetor - Google Patents

Description

P. KOLLSMAN Oct. 24, 1950 cARBuREToR i s'shee'ts-shee: 1

Fil'ed Feb. 28, 1946 Och 24, 1959 P. KoLLsMAN 2,526,673

CARBURETOR I Filed Feb. 28, 194e" shew-Sheer. 2

ct. 24, 1950 p, KQLLSMAN 2,526,673

CARBURETOR Filed Feb. 28, 1946 3 Sheets-Sheet 5 Patented Oct. V24, 1950 UNITED STATES PATENT OFFICE CARBURETOR Paul Kollsman, New York, N. Y. Application February 28, 1946, Serial No'. 650,868

This invention relates to carburetors, particularly for internal combustion engines and has, more generally, application to devices for producing a mixture of a gas and a liquid.

Among its various objects and features the invention provides a carburetor or similar device in which a certain quantity of a liquid is proportioned to a certain quantity of a gas, the proportions being so regulated that at all times the weight flow or mass flow of the liquid maintains a predetermined ratio to the weight ow or mass flow of the gas regardless of changes in density.

The invention further provides various features and improvements of control, of mixing of a gas and a uid, and other features and novel details of particular value and application to carburetors for internal combustion engines.

The various objects, features and advantages of this invention will appear more fully from the detailed description which follows, accompanied by drawings, showing for the purpose of illustration a preferred embodiment of the invention.

The invention also consists of certain new and original features of construction in combination of parts as hereinafter set forth and claimed.

Although the characteristic features of this invention which are believed to be novel will be particularly pointed out in the claims appended hereto, the invention itself, its objects and advantages, and the manner in which it can be carried out may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part of it, in which:

Fig. 1 is a sectional side elevation of a carburetor embodying the invention, the section being taken on line I--I of Fig. 2;

Fig. 2 is a plan view of the carburetor shown in Fig. 1;

Fig. 3 is a side elevation of the carburetor shown in Figs. 1 and 2;

Fig. 4 is a section taken on line 4 4 of Fig. 1;

Fig. 5 is a section taken on line 5 5 of Fig. 1;

Fig. 6 is an enlarged sectional view of a detail of the carburetor shown in Fig. 1, the section being taken on line 6 6; and v Fig. '7 is a detailed view of a spring loaded throttle valve of the apparatus shown more particularly in Figs. 1 and 3.

In the following description and in the claims, various details will be identified by specific names for convenience, the names, however, are intended to be as generic in their application as the art will permit. Like reference characters refer to like parts in the several gures of the drawing.

4 Claims. (Cl. 261-28) In the drawings accompanying and forming part of, this specification, certain specific disclosure of the invention is made for the purpose of explanation of broader aspects of the invention, but it is understood that the details may be modifled in various respects without departure from the principles of the invention and that the invention may be applied to, and practiced by other structures than the one shown.

In the description, the term pressure uid or uid will be used as a, generic term, denoting non-compressible as well as compressible fluids, for example, liquids and gases, and mixtures 'of liquids and gases.

Referring to the drawing, the apparatusshown in Fig. 1 comprises aY housing Il having an inlet flange I2 leading to an inlet passage I3 and `an outlet flange I4 at the end of an outlet passage I5. The outlet passage I5 is normally connected to a point of reduced pressure, for examplethe intake duct I6 of an internal combustion engine indicated in dotted lines in Fig. 3. The inlet passage of the apparatus leads toa'point of atmospheric pressure, for example, Athe conventional intake air filter commonly used for carburetors of internal combustion engines.

A central stud'I'I in the inlet passage supports a drive shaft I8 in bearings I9 and 20. The shaft I8 is driven by a motor 2I secured to the housing by screws 22, and carries at its end animpeller, 23 having substantially radial blades 24. The motor 2l is preferably a constant speed motor although this is not necessary,

The impeller 23 is in the nature of a rotor of a centrifugal pump and imparts to the air or gas passing through the intake duct I3 a rotary m'otion about the axis of the drive shaft I8.

A rotor 25 having a shaft 26 is supported in bearings 21 and 28. The rotor 25 has a plurality of substantially radially extending vanes 29 adjacent the periphery of the impeller 23. Air or gas issuing from the blades 24 of the impeller impacts upon the vanes 29 of the rotor and exerts a certain reactive torque thereon tending to turn the rotor about its axis.

A rotary valve member 3D in the valve member 3! is xed on the rotor shaft 26 and has a control edge 32 adapted to cover and uncover a control port 33 leading to a control duct 34. Details of this valve are shown in greater detail in Figure 6. Air or gas of substantially atmospheric pressure may enter the valve chamber 3| through a passage 35.

Air leaving the vanes 29 of the rotor 25 enters an annular chamber 36 and thence flows through passages 31 into an enlarged air chamber 38 separated from the outlet passage I by a movable throttle valve member 39.

A liquid, for example gasoline, is supplied to the regulator through a supply duct 49 leading to a pipe connection 4I in the housing II. A duct 42 leads from the pipe connection 3l to a central chamber 43 in which a further impeller 44 turns. The impeller 44 is mounted on a shaft 45 supported in bearings 4S and 41. A drive pinion 43 is secured to the end of the impeller shaft and meshes with an intermediate gear 49 on a stud shaft 59. The intermediate gear, in turn, meshes with a further gear 5I on a shaft 52 extending through the length of the housing II and turning in bearings 53 and 54. The other end of the shaft 52 carries the pinion 55 meshing with a drive gear 58 on the drive shaft I8 of the motor 2l, It is thus evident that the irnpeller 23 in the gas passage and the impeller 44 in the liquid passage are driven at a constant speed ratio which is maintained at all times even if the speed of the motor 2l may change;

The liquid impeller 44 has substantially radially extending blades 51 adapted to impart a circular motion about the drive shaft 45 to the particles of liquid flowing through the duct 42 and entering the impeller.

The impeller 44 is Surrounded by substantially radially extending vanes 58 of a rotor or fluid obstacle 59. The rotor 59 is mounted on a shaft 69 rotatable in bearings 6I and 62. A permanent magnet E3 on the end of the rotor shaft 59 is magnetically coupled through a wall E4 in the housing II with a similar magnet -65Y on the end of the shaft of the rotor 25associated with the air impeller 23.

The intermediate gear 49- in the drive of the liquid impeller 44 causes the liquid impeller to spin in a direction opposite to that of the a-ir impeller 23.. As a result, a torque is exerted by the impact of the accelerated liquid particles on the Vanes of the rotor 59 which is opposed tothe direction of the torque exerted by the rotor 25 acted upon by air. The torque of the rotor is transmitted to the rotary Valve member 3l]l by the magnetic coupling 63, G5 acting through the liquid-tight wall 64 of the housing. It is evident that if the torque exerted on the liquid rotor 59 vis equal to the torque exerted on the air rotor 25, the rotary valve 39 will not move with respect to control port 33.

A floating disk 63 is freely rotatable on an extension 61 of the rotor shaft 45 to decrease the drag which would otherwise be exertedV on the rotor 59 by liquid friction between Yit and thek impeller 44. Liquid particles accelerated by the outer wall of the impeller 4'4 exert a certain drag on the floating disk 66 causing the disk to rotate very slowly on'the shaft extension 61. The disk 69 is braked by the liquid between it and thewall of the rotor 59 which for practical purposes may be considered as stationary. The dragl exerted by the disk 68 on the adjacent wall of the rotor 59` is negligible due to the greatly reduced rate a-t which the disk turns.

Air at approximately atmospheric pressure enters the valve chamber 3| of the rotary valve 30 through the passage 35. Air is withdrawn from the Valve chamber 3| through the control duct 34 which communicates with a branch duct 88 leading to a constricted passage 69 opening into the air outlet I5. Since the outlet passage I5 is a. point ofA reduced pressure due to its connection to.` the intake of a combustion engine or to some other source of suction, a reduced control pressure is created in the branch duct 98 and the control duct 34. The control pressure is equal to the pressure existing at the constricted passage 59 when the rotary valve 39 is closed, and ranges up to nearly'atmospheric pressure when the rotary Valve 38 is fully open. It thus becomes evident that the pressure in the control duct 34 is controllable by the rotary valve 39 and thus becomes a function of the torque differential of the air rotor 25 and the liquid rotor 5S.

The control duct 34 leads to a diaphragm chamber 1D one wall of which is formed by a flexible diaphragm 1 I The diaphragm separates the chamber 'l0 from a further chamber 12 communicating with a point of substantially atmospheric pressure through a conduit 13 leading to a port 14 in the inlet passage I 3.

The diaphragm 1I acts upon a movable valve member 'l5 guided in a sleeve 16 and controlling a valve port 11. The diaphragm 1I tends to keep the valve port 'I1 closed when equal pressures exist in the chambers 19 and 12. The valve port 1l' opens if reduced pressure acts on the diaphragm in chamber 19 causing the diaphragm to deflect to the right. This condition is brought about by closing of the control valve port 33 by the rotary valve member 30 permitting maximum suction to be applied to the chamber 10 through the branch duct 68 and the constricted passage 59.

Liquid leaving the vanes 58 of the rotor 59 enters an annular chamber "I8 communicating with a further annular chamber I9 through passages 38. The liquid flows from the annular chamber i3 through a duct BI leading to the control valve 15, 11. A controlled quantity of liquid is admitted through the control port 'l1 and enters a duct 82 leading to a nozzle 83 in the air chamber 38 at a point near the throttle valve 39, which is a point at which the air or gas travels at a relatively high velocity to insure intimate mixture between the airand the liquid injected therein.

Liquid flowing through the valve 15, 11 is prevented from entering the diaphragm chamber 12 by a bellows or sylphon 84 between the diaphragm 1I and an annular wall 85 in the housing.

Mixture of gas and liquid, for example of air and liquid fuel is withdrawn through the outlet passage I5 controlled by the throttle valve 39. The throttle valve 89 is mounted on a shaft 86 freely rotatable in the housing and is acted upon by a spring 81 (see Fig. 7) one end of which is secured to the shaft 86, the other end being secured to a post 88 on the housing I I. The spring 87 tends to keep the throttle valve 39 closed. The throttle valve member 39, on the other hand, is acted upon by the differential pressure across the valve member 39, that is by suction in the outlet passage I5 and by the pressure of the air or gas in the chamber 38. Since normally the pressure in the outlet passage I5 is lower than the pressure in the air chamber 38, the valve member 39 opens until a condition of equilibrium is attained in which the force exerted on the valve member 39 by the pressure differential between the outlet passage I5 and the air chamber 38 is equal to the force of the spring 81 tending to move the valve member in the opposite direction.

The position of the valve member 39 is further controlled, and its free movement limited, by limit stop means which may be pre-set from the outside. Details of the stop arrangement are illustrated in Fig. 3.

A pre-settable arm B9 is mounted on the casing for pivotal movement coaxially with the valve shaft 86. The position of the arm 89 is adjustable by a rod 9|] leading to a suitable control lever or segment (not shown). A screw 9| is adjustable in the arm 89. A valve arm 92 is secured to the end of the valve shaft 86 and cooperates with the screw 9| forming a stop for the arm limiting the movement of the valve arm 92 in counter-clockwise direction. The extent of opening movement of the Valve 39 under differential pressure is thus adjustable by the arm 89.

The operation of the fluid ratio regulator is as Yfollows: Air is admitted through the inlet passage I3 and passes through the i-mpeller 23 Whose velocity of the impeller 23. The accelerated air particles leaving the blades of the impeller 23 strike the vanes 29 of the rotor and thus Ylose their tangential velocity. The impact force exerted on the Vanes of the rotor thus becomes proportional to the tangential velocity of the air flow multiplied by its mass. The tangential velocity being constant the impact or torque exerted on the rotor becomes a function of the mass flow of the air owing through the inlet passage I3.

Liquid fuel admitted through the ducts and 42 enters the impeller 44 and is likewise accelerated to a tangential velocity equal to the circumferential speed of the liquid impeller 44 which bears a fixed relation to the circumferential velocity of the air impeller 23. The accelerated liquid particles strike the vanes 58 of the rotor 59 and tend to turn the rotor in direction opposite to the rotor 25.

The liquid fuel leaving the vanes of the rotor 59 ows through the passage 8| to the fuel valve 15, 11 vand thence through the duct 82 to the fuel nozzle 83 for injection into the air stream flowing through the outlet passage |5.

Assuming the torque exerted by the air on the rotor 25 is equal to the torque exerted by the liquid on the rotor 59, the two torques cancel out at the magnetic coupling 63, 85 between the rotor shafts 26 and 50 and the rotary Valve 38 does not move. If the amount of fuel flowing through the apparatus is momentarily less than the amount to be maintained with respect to the air, the torque exerted on the liquid rotor 59 is reduced, causing the rotary valve member 39 to turn under action of the air rotor 25, reducing the'area of the control port 33 to which air is admitted into the control duct 34. The result is al drop in pressure in the control duct causing deection of the diaphragm 1| to the right and movement of the Valve member to a position in which an increased flow of liquid is admitted through the valve 15, Il. The flow of fuel is increased until the normal ratio of the weight flow of fuel with respect to the weight flow of air is re-established. When the correct ow is established, the reaction of the liquid on the rotor 59 is increased to an amount equal to the torque exerted by the air rotor 25 with the result that the forces exerted by the magnets 63 and 65 are equal and opposed. The regulator is now in equilibrium. It is evident that the equilibrium is not affected by changes in the speed of the motor 2 since an increase or decrease in the motor speed causes a proportional increase and decrease in the speeds of both impellers 23 and 44.

Assuming now for example that for some reason the amount of air owing through the regulator be decreased, it is apparent that as a consequence, the torque exerted on the air rotor 25 is decreased permitting momentarily the liquid rotor to adjust the rotary valve 30 through the magnetic coupling 63, 95. As a result the control port is opened further causing an increase in pressure in the control duct 34. The increased pressure moves the diaphragm 1| to the left whereby the flow of liquid is correspondingly decreased. It is thus evident that a constant ratio between the Weight flow of two fluids, air and liquid is automatically maintained.

In the illustrated embodiment of the invention the amount of air flowing through the regulator is determined by the demand of the internal combustion engine connected to the outlet flange I4.

If the demand increases` the differential pressure across the throttle valve member 39 `increases causing the valve member automatically to open further if the stop 9| permits. Reduction in the demand of air and fuel mixture causes a decrease in the pressure and the outlet passage |5 and a corresponding movement of the throttle valve 39. The limits of the movement of the throttle valve may be set by appropriate adjustment of the arm It will be noted in this connection that the throttle valve 39, unlike conventional throttle valves, is not directly actuated as it is for example by the accelerator pedal of an automobile. In the illustrated apparatus the throttle yvalve member adjusts itself automatically in dependence on the differential pressure acting on it. Thus forceful rapid opening of the throttle valve beyond its proper position is prevented which, as is well known, causes an abnormal increases in pressure: at the carburetor nozzle 83 accompanied by a substantial decrease in air velocity resulting in incomplete atomization and unsatisfactory mixture between air and fuel. In the illustrated carburetor, substantial air velocities are maintained at all times at the point where fuel is injected into the air stream and complete mixing between air' and fuel is thus insured.

An adjustment of the arm 89 moving the stops 9| corresponds to the direct actuation of the` throttle valve in conventional carburetors. In ther present instance, however, adjustment of thelimit stops towards the open position permits automatic' increased opening of the throttle valve 39 without forcing the throttle valve member so to move immediately. After adjustment of theV stops towards the open position, the throttle valve member opens automatically in response to the differential pressure acting on it but not so fast as to cause the pressure differential between the outlet passage I5 and the air chamber 3B to drop to practically Zero, a condition often present in conventional installations which leads to incomplete atomization of the fuel. Restriction of the rate of opening of the throttle valve 39 is a particular feature of the invention.

If the flow of combustible mixture is to be decreased the limit stop is moved in the opposite direction. This causes forcible adjustment of the throttle valve 39 towards the closed position. Forcible movement in this direction, however, does notvhave the injurious consequences which forcible opening has and is for this reason not objectionable.

Regardless of whether the now through the outlet passage I5 is, increased or decreased, the regulator operates to maintain a predetermined ratio of gas to liquid, or. air to fuel, constant. The ratio of flows is not affected by changes in density since the flow responsive members of the appa. ratus are responsive to the mass ow, or weight flow', rather than the volume ow. It is for this reason possible to employ the invention. advantageously for the control of fluids which undergo substantial changes in density. Apparatus ernbodying the invention are admirably suited for proportioning ows of liquid which occasionally or constantly are mixed with gas. Since the control of the apparatus is not affected by such mixtures it remains at all times responsive to the actual mass flow.

While the illustrated embodiment shows the application of the invention to the control of the flow of a liquid with respect to the flow of a gas, it is evident that the invention is not limited thereto. The ratio of several liquids may be controlled in the same manner as may be the ratio of several ows of gas.

The illustrated embodiment of the invention is particularly adapted for use in connection with carburetors for internal combustion engines. Advantage is taken in the illustrated construction of the particular conditions present in carburetor installation to operate certain elements of the regulator. For example, the pressure difference between the outlet passage I and the inlet passage I3 is utilized for operating the diaphragmactuated valve l0, l5, 'il through the control valve 30, 33. In the illustrated form of invention the actuating diaphragm 'i0 constitutes a servomotor and the pressure uid valve 30, 33 represents a convenient form of relay for actuating said servo-motor.

The energy imparted to the liquid particles is conveniently measured in the illustrated regulator by reaction exerted on a rotor. However, the amount of energy required for imparting a predetermined accelerationto the mass of the uid is also proportional to the torques required for driving the respective impellers for the various fluids, the torques bearing the same relation as the reaction forces exerted by the fluids against the iiuid obstacles which the rotors represent.

It thus becomes evident that the invention may be applied to and practiced by various forms of apparatus but is not limited to the specific device illustrated in the drawings. Thus numerous changes, additions, omissions, substitutions and modifications may be made without departing from the spirit, teaching and principles of the invention.

What is claimed is:

1. A carburetor comprising, in combination, an air passage; a throttle valve in said air passage; a nozzle discharging into said air passage; a fuel supply duct leading to said nozzle; a fuel supply valve for controlling the supply of fuel flowing through said duct to said nozzle; means for imparting to the particles of air flowing through said duct a predetermined acceleration; means for imparting to the particles of fuel flowing through said duct a predetermined acceleration; common drive means for said acceleration imparting means; a movable fluid obstacle acted upon by the accelerated ilow of air; a movable obstacle acted upon by the accelerated flow of fuel; and an actuating member acted upon by said two fluid vobstacles in opposite sense for actuating said fuel supply valve.

2. A carburetor comprising, in combination, an air passage; a throttle valve in said air passage; a nozzle discharging into said air passage; a fuel supply duct leading to said nozzle; a rotary impeller in the path of the air flowing through said passage; a rotor acted upon by air leaving said impeller; a rotary impeller in the path of the fluel flowing through said duct; a rotor acted upon by fuel leaving said fuel impeller; means for driving said two impellers at a constant ratio of speeds; and a fuel' supply valve for controlling the supply of fuel flowing through said duct to said nozzle, said fuel supply valve being acted upon by both of said rotors.

3. A carburetor comprising, in combination, an air passage; means for controlling the flow of air therethrough; a nozzle discharging intosaid air passage; a fuel supply duct leading to said nozzle; means for controlling the supply of fuel through saidl duct to said nozzle; means for imparting to the particles of the airv ilowing through said air passage a predetermined acceleration; means for imparting to the particles of the fuel flowing through said duct a predetermined acceleration proportional to the acceleration imparted to said air particles; a first means movable angularly in response to the energy imparted to the accelerated air; a second means movable angularly in response to the energy imparted to the accelerated fuel; and actuating means jointly and oppositely acted upon by said first responsive means and said second responsive means for actuating at least one of said control means.

4. A carburetor comprising, in combination, an air passage; a throttle valve in said air passage; a nozzle discharging into said air passage; a fuel supply duct le-ading to said nozzle; a fuel supply valve for controlling the supply of fuel flowing through said duct to said nozzle; means for imparting to the particles of air flowing through saidpassage a predetermined acceleration; means for imparting to the particles of the fuel ilowing through said duct a predetermined acceleration; common drive means for said acceleration imparting means; a rst means movable angularly in response to the energy imparted to the accelerated air; a second means movable angularly in response to the energy imparted to the accelerated fuel; and actuating means jointly and oppositely acted upon by said rst responsive means and said second responsive means for actuatingV said fuel supply valve.

PAUL KOLLSMAN.

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

UNITED STATES PATENTS Number Name Date 2,013,932 Viel Sept. 10, 1935 2,139,841 Mennesson Dec. 13, 1938 2,160,309 Huffman May 30, 1939 2,369,665 Gosslau Feb. 20, 1945 2,395,648 V'l'eichert Feb. 26, 1946 2,403,866 Lipfert July 9, 1946 2,416,907 Chandler Mar. 4, 1947

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