US1475719A - Carburetor - Google Patents

Description

J. W. PARMN CARBURETOR Filed Fe vl 1922 2 Sheets-Sheet 1 IN VE N TOR U215 ep7z/ WfarRm Nov. 27, 1923. 1,475,719 J. w. PARKIN GARBURETOR Filed Feb. '7, 1922 2 SheetsSheet 2 ATTO NE) Patented Nov. 27, 1923.

JOSEPH W. PARKIN F PHILADELPHIA, PENNSYLVANIA.

CARBURETOR.

Application filed February 7, 1922. Serial No. 534,684.

To all whom it may concern Be it known that I, .losicrn \V. PARKIN. a citizen of the United States. residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Carburetors, of which the following is a specification.

The object of this invention is to provide a carburetor for internal combustion engines with novel, simple and efiicient means under the control of different degrees of suction created within the carbureting passage to automatically regulate the supply of liquidv the mixture outlet of the carbureting pas-' sage, in combination with means acting independently of" the throttle valve and controlled automaticallyby different degrees of suction created within the carbureting passage for causing the fuel discharge openings successively to'conti 'ol the supply of fuel to the carbureting passage.

With the above and related objects in view, the invention consists of the elements and combinations of the elements of the carburetor as will be hereinafter described and claimed.

In the accompanying drawings, illustratin the invention,

igure 1 is a side view of a carburetor embodying my invention.

Figure 2 is a top view thereof.

Figures '3 and 4 are vertical sections thereof, on lines 33 and 4-4, of Figs. 2 and 1, respectively.

Referring to the drawings, 2 designatesa casing having formed therein a carbureting passage 5 and a chamber 6 for the reception of gasoline or other suitable liquid fuel.

The carbureting passage 5 is divided into an inlet end nortion 7 and an outlet end portion 8 of cross sectional than that of the portion 7. The outlet end portion 8 is adapted to be connected to the intake passage or manifold of an internal combustion engine. so that. during, the operation of the engine. air will be drawn into and through the carbureting passage 5 in the usual anner. I

The entrance to theinlet portion 7 of the passage 5 is provided with a suitable choke valve 9 for the usual purpose, and the exit of the outlet portion 8 of the passage 5 provided with a suitable throttle valve 10 for varying, in the usual manner, the degree of suction created within the passage 5 by the engine.

The top of the fuel chamber 6 is closed by a removable cap or cover 11 which is secured to the casing 2 by cap screws 12.

A chamber 21 is formed on the cover 11 by a transparent cylinder 14 which with lower and upper packing washers 13 and 15, respectively, is clamped between the cover 11 and a head 17 having a stem 18 screwed into a projecting post 19 on the cover 11.

Liquid fuel is supplied to the chamber 6 through a pipe 22 screwed into the cover 11. apassa ge in the cover 11, the ihamber 21, passages 23 and 24 in the post 19 and a passage 25 in a stem 26 screwed into the cover 11.

A float 33 slidable on a fixed guiding post 34 within the chambei' tl maintains the liquid fuel at a predetermined level therein by a bracket 32, carried by the float 33, engaging a valve pin 29 whose upper end closes the passage 25 wh n the float 33 is raised. The valve pin 29 slides within an opening in the lower portion 28 of the stem 26 and is provided with a transverse pin 30 which extends into an opening 27 in the stem 26 and prevents the valve pin 29 from falling from the stem 26 when the cover 11 is removed from the casing 2.

Downward movement of the float 33 is limited by the engagement of the bracket 32 with the top of the post 34; and a screen 31 surrounding the post 19 prevents dirt and foreign substances from entering the passage 23 with the liquid fuel.

The lower portion of the chamber 6 communieates with a passage 35 which extends outwardly through the casing 2'and terminates in a part or plug 36 having a fuel passage therein screwed into the casing 2.

The part 36 discharges into a transverse passage 37 having two spaced, upwardly extending branches 38 and 39 formed in parts of the casing 2. The upper ends of the passages, 38 and 39 terminate in nozzles 40' and 41 formed by plugs which are screwed into the casing from wi hin the carbureting passage Thelevel of liquid fuel automatically maintained by thefloat 33 within the chamber 6 and the passage 37 and its branches 38 and 39 is a slight distance below the top of the main fuel nozzle 40. The member 32 is formed of bendable metal of a character which will remain. in the shape or condition into which it is bent and be of sufiicient stiffness to perform its function. It will therefore be understood that by bending the member 32 to raise or lower that portion thereof which extends between the post 34 and valve 29 the level ofliquid fuel automatically maintained by the float 33 may beraised or lowered for the attainment of the best results.

The fuel nozzle 40 discharges into the outlet portion 8 of the passage 5 and the fuel nozzle 41 discharges into the inlet portion 7 of the passage 5 at a higher level than that of the nozzle 40, as shown in Fig. 3, to prevent suction within the passage 5 from accidentally drawing liquid fuel from the nozzle 41 when it is not desired. The opening in'the part 36 which controlsthe quantity of liquid discharged therethrough is of greater cross sectional area than that of the nozzle 40 and of less cross sectional area than that of'thc nozzle 41 for purposes hereinafter explained, and the upper end portions of the openings or passages of the nozzles 40 and 41 are flared outwardly, as shown.

The cross sectional area of the passage 37 and of each of its branches 38 and 39 is greater than that ofthe opening in the supply part 36 to provide storage space for.

liquid fuel to be supplied to the nozzle 41, as .will hereinafter appear.

The effective cross sectional area of the passage5=betweenthe nozzles 40 and 41 and between the nozzle 41 and the throttle valve 10 is varied and controlled by a valve 42 which operates automatically under the influence of different degrees .of suction created within the passage 5 by the operation of the engine at different speeds. The valve 42 comprises a plate secured toand extend- -ing above and below a shaft 43 which is mounted toturn inbearings formed by a cap or cover 44 which is secured upon the casing 2 over the passage 5 by cap-ascrews 45. The cover 44 closes an opening in the top wall of the inner end of the outlet portion 8 of the passage 5 through which the lower portion of the valve plate 42 extends.

The upper end portion of the plate 42 is adapted to wol -rk within a cavity or opening formedi'n i' -the cover 44, and the lower portion of the plate 42 is adapted to move toward @Iljd froma closed position against a. transverse wall 46 at the meeting ends inner. end portion of the spring 47 is inserted into an opening in the cover 44, and the outer end portion of the spring 44 is in;

serted'into' an opening in a head 48 on the shaft43. The head 48 is prevented from turning relatively to the shaft 43 by a pin 49 which extends transversely through the shaft 43 and engages the walls of oneof two pairs of alined radial "grooves 50 formed in the outer end of the head 48. The spring 47 not only acts to turn the shaft 43 and press the valve plate 42 toward the wall 46 but it also exerts an outward pressure against the head 48 and prevents accidental disengagement of the head 48 from the pin 49. The degree of pressure of the spring 47 against the valve plate 42 maybe regulated by pressing the head 48 inwardly to disengage it from the pin 49, turning the head 48 to vary the spring pressure, and 'then re-engaging the head with the pin.

The movement of the valve plate 42 toward the wall 46 or closed position is limited by the inner end of an adjustable stop screw 51 which is adapted to be engaged by the upper end portion of the plate 42; to control the initial position of the valve and the movement of the valve plate 42 away fromthe wall 46 ,is limited by the lower end of an adjustable stop screw 52 which is adapted to be engaged by the lower end 'portionof the plate 42 to control the wide walls 53 and 54 of the cover 44, and the parts of the split walls are adapted to be drawn together to lock the stop screws in different positions of adjustment by suitable locking screws 55 and 56, respectively, adapted to draw the parts of the split walls together to lock the stop screws therein.

The operation of the carburetor is as follows:

When the engine is idling or running at slow speed under alight load the upper end of the valve plate 42 is engaged, with or close to the stop screw 51 and the lower portion of the valve plate 42 is close to its closed position reducing the effective cross sectional area of the passage 5 between the nozzles 40 and 41 to a considerable extent, causing the suction created within the passage 5 by the engine to draw gasoline or liquid fuel only from the nozzle 40 and mix it with the air being drawn into and through the carbureting passage 5. The small opening of the nozzle 40 controls the desired small quantity of liquid fuel required for slow engine speed nozzles 40 and 41.

When the throttle valve 10 is opened to increase the engine speed, increased suction is created within the carbureting passage 5 and such increased suction draws the valve plate 42 toward the stop screw 52 against the action of the spring 47 and increases the effective cross sectional area of the passage 5 in the region of the nozzle 40. During the movement of the valve plate 42 toward the stop screw 52 the increased suction continues to draw liquid fuel from the nozzle 40 until the valve plate 42 reaches a position in which the suction over the nozzle 41 is greater than the suction over the nozzle 40, due to the reduced position of the valve 42 and the cross sectional area of inlet portion 7 of the passage 5 into which the nozzle 41 opens. When the suction over the nozzle 41 is great enough to draw liquid fuel therefrom, the suction over the nozzle 40 has been reduced sufiiciently to prevent it from drawing fuel therefrom and the quantity of fuel supplied to the passage 5 is increased and governed by the opening of the nozzle 41 which is larger than the openingof the nozzle 40. As the open ing of the nozzle 41 is also larger than the opening of the part 36 the fuel supplied through the nozzle 41 is not only drawn from the chamber 6 through the part 36 but also from the well or branch 38 of the passage 37 until the branch 38 is emptied and the part 36 governs the quantity of fuel being supplied to the passage 5 through the larger opening of the nozzle 41. After the suction begins to draw fuel through the nozzle 41, the quantity of fuel rawn into the carbureting'passage 5 is limited only by the opening of the nozzle 41 until there is insuflicicnt fuel within the passage 37 and its branches 38 and 39 to supply the nozzle 41 at its full capacity, and, t ereaftelgthe quantity of fuel supplied through the nozzle 41 is reduced and governed by the part 36 under increased suction created within the carbureting paS- sage by the engine as it reaches and continues to operate at high speed.

It will now be understood that when the engine is running at low speed or idling the opening of the nozzle 40 will govern the quantity of liquid fuel supplied to the carbureting passage 5, that when the engine is running at high speed the opening of the part 36 will govern the quantity of liquid fuel supplied to the passage 5, and that during the pick 11 or intermediate speeds between the low and high speeds the opening of the nozzle 41 at its maximum capacity will govern the quantity of liquid fuel supplied to the passage 5, automatically supplying the desired rich mixture for intermediate speeds or a quick pick up when the load'is on the engine, and, thereafter, automatically re ducing the quantity of liquid fuel for the best results after the engine reaches and continues to operate at high speed. As the speed of the engine decreases either by moving the throttle valve 10 toward its closed position, or by a heavy load upon the engine, the air valve 42 automatically moves back toward its closed position, the liquid fuel fills both branches 38 and 39 of the passage 37 and the carburetor is again ready to be operated for another increase in engine speed.

It will be observed that the air valve 42 is free to move either toward its initial position against the stop screw 50 or toward its full open position against the stop screw 52 independently of the throttle valve 10, permitting the valve 42 to move toward its full open position for the regulation of the liquid fuel supply as the engine increases its speed due to a reduction of the load thereon while the position of the throttle valve 10 remains unchanged, and permitting the valve 42 to move back toward its initial position for the regulation of the liquid fuel supply as the engine decreases its speed due to an increased load thereon while the position of the throttle valve remains unchanged.

After high speed has been reached and when the part 36 is in control of the quantity of gasoline being supplied to the carbureting passage 5, the suction created within the passage 5 not only draws liquid fuel from the part 36 through the passage-37, its branch 39 and nozzle 41, but it also draws air down through the nozzle 40, branch passage 38, passage 37, branch passage 39 and nozzle 41 for a preliminary mixture before the liquid fuel enters the carbureting passage 5, thereby assisting in the vaporization of liquid fuel.

I claim as my invention:

1. A carburetor comprising a casing having a carbureting passage provided with an air inlet and a mixture outlet, a throttle valve controlling the mixture outlet, a main fuel nozzle having a discharge opening communicating with said passage, a second fuel nozzle. communicating with said passage be tween the main nozzle and the throttle valve and having a discharge opening of less cross sectional area than that of the main nozzle, 'a fuel feed controlling part discharging into a divided passage which leads to said nozzles. said p ha ing a discharge opening of less cross secnonal area than that of the main nozzle and of great ""oss s ctional area than that of the scoop. named nozzle, means to supply liquid fuel t'o said part. and a yieldable valve associated wit the carbureting passage and arranged to ct automatically under the influence of progressively increasing degrees of suction created therein to vary the effective cross sectional area of the carbureting passage between the main nozzle and the throttl valve.

2. A carburetor comprising a casing having a carbureting passage provided with an air inlet and a mixture outlet, a throttle valve controlling the mixture outlet, a main fuel nozzle having a discharge opening communicating with said passage, a second fuel nozzle communicating with said passage between the main nozzle and the throttle valve and having a discharge opening of less cross sectional area than that of the mainnozzle, a fuel feed controlling part discharging into a divided passage which leads to said nozzles, said part having a discharge opening of less cross sectional area than that of the main nozzle and of greater cross sectional area than that of the second named nozzle, means to supply liquid fuel to said part, a yieldable valve associated with the carbureting passage and arranged to act automatically under the influence of progressively increasing degrees of suction created therein to varythe effective cross sectional area of the carbureting passage between the main nozzle and the throttle valve, and means for adjusting the initial position of the yieldable valve.

3. A carburetor comprising a casing having a carbureting passage provided with an air inlet and a miir'ture outlet, a throttle valve controlling the mixture outlet, a main fuel nozzle having a discharge opening communicating with said passage, a second fuel nozzle communicating with said passage between the main nozzle and the throttle valve and having a discharge opening of less cross sectional area than that of the main nozzle,

a fuel feed controlling part discharging into a divided passage which leads to saidnozzles, said part having a discharge opening of less cross sectional area than that of the main nozzle and of greater cross sectional area than that of the second named nozzle,

means to supply liquid fuel to said part, a yieldablevalve associated with the carbureting passage and arranged to actautomatically under the influence of progressively increasing degrees of suction created therein to vary the effective cross sectional area of the carbureting passage. between the main nozzle and the throttle valve, and an adj ustable spring opposing the opening of the yieldable valve.

4. A carburetor comprising a casing having a carbureting passage provided with an air inletand a mixture outlet, a throttle valve controlling the mixture outlet, a main fuel nozzle having a discharge opening communicating with said passage, a second fuel nozzle communicating with said passage between the main nozzle and the throttle valve and having a discharge opening of less cross sectional area than that of the main nozzle, a fuel feed controlling part discharging into a divided passage which leads to said nozzles, said part having a discharge opening of less cross sectional area than that of the main nozzle and -of greater cross sectional area than .that of the second named nozzle, means to supply liquid fuel to said part, and a spring pressed valve pivotally connected to the casing above the nozzles and having a .lower end portion movable from a position between said nozzles toward and from the throttle valve and arranged to'act automatically under the influence of progressively increasing degrees of suction created therein to vary the effective cross sectional area of the carbureting passage.

5. A carburetor comprising a casing hav' ing a carbureting passage provided with an 'air .inlet and a mixture outlet, a throttle valve controlling the mixture outlet, a main fuel nozzle having a discharge opening communicating with said passage, a second fuel nozzle communicating with said passage between the main nozzle and the throttle valve andh ving a discharge opening of less cross sectioili'al area than that of the main nozzle, a fuelfffeed controlling part discharging into a divided passage which leads to said .nozzles, said part having a discharge opening of less cross sectional area than that of the main nozzle and of greater cross sectional area than that of the second named nozzle, means to supply liquid fuel to said part, a spring pressed valve pivotally connected to the casing above the nozzles and having a lower end portion movable from a position between said nozzles toward and from the throttle valve and arranged to act automatically' under the influence of progressively in creasing degrees of suction created therein to Vary the effective cross sectional area of thecarbureting passage, means for adjusting the initial position of the spring pressedvalve, and an adjustable spring opposing the opening of the last named valve.

In testimony whereof I affix my signature hereto.

' JOSEPH W. PARKIN.

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