US1398707A - Carbureter - Google Patents

Description

H. K. TARKINGTON.

CARBURETER.

' APPLICATION FILED 0CT=18, 1916. 1,398,707. Patented Nov. 29, 1921.

3 SHEETS-SHEET l.

- H. K. TARKINGTON.

CARBURETER APPLICATION FILED OCT. 18, I916.

Patented Nov. 29

3 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

HARRY TARKIN'GTON, OF CHICAGO,

nJLmoIs, iassieivon or ONE-HALF 'ro H(')W'.ARD L. BABCOCK, OF CHICAGO, ILLINOIS.

I cannunn'rnn.

To all whom-it may concern:

Be it known that I, HARRY K. TARKING- TON, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Carbureters, of which the following is a specification.

This invention relates to improvements in carbureters of the general type employed with internal combustion engines for the 'production of the explosivecharge thereof; .and it has as its main and primaryobject the provisionof a device of this character, the construction of which is such as to dispense with the use offioat chambers and theirappurtenances and to substitute therefor a construction operating under variable pressure. f

The use of float chambers in carbureter construction is attended with many difi culties. Notable among the same is the frequentflooding of the carbureter due to the sticking of the float, resulting in fire risk and attendant loss 0 the hydrocarbon fuel, and likewise the abs rptionby the float of the liquid fuel destroys its buoyancy and precludes proper control of the fuel through the instrumentalities associated with the float. These difiiculties are recognized more pronouncedly in the manipulation of automobiles'in which the operation of the carbureters is frequently impaired 'by theconditions recited.

The present invention therefore seeks to provide a carbureter which is designed to overcome the conditions noted, and in which the feed of the liquid fuel is induced and "controlled by the suction of the engine pistons, which suction operates to create a vacuum condition within -the .carbureter.

The feed is therefore proportionate to the 1 speed of and load upon the engine and only somuch of tlieluel is utilized as is actually required. 1 1 .The invention further aims to provide a carbureter having simple .and novel means for controlling the flow ofthe fuel proportionately to the range of operation of the throttle valve, whichcontrol may be effected both manually and automatically,'whereby to graduate the quantity of the fuel required for varying load conditions and to insure Specification of Letters Patent. Patented Nov. 29, 1921.

Application filed October-18, i916. Serial'Ro. 126,238. W '1 a proper minturein the production of the 4 explosive charge.

Furthermore, the invention also has in view the production of a carbureterhaving minimum.

Witlfthese "general objects in view, and others which'will ap ar as the nature of the improvements is etter understood, the invention consists substantially in the novel construction, combination and arrangement of parts hereinafter fully described,

illustrated in the accompanying drawings,

and finally pointed out in the appended claims. v

ile the forms of the invention herein shown and described are believed to be preferable embodiments thereof,it is to be understood-that the same merely'depict particular adaptations. The. invention is susceptible of various changes and modifications, and in the presentation of these embodiments it is understood that no limitations upon the invention itself necessarily inhere therein, but the right is reserved to change, modify or vary. the invention within the scope of the claims. Q

.In the. accompanying drawings Figure l is a side elevation of a carbureter' constructed in accordance with the principles of, the present invention. I

Fig. 2 is a. similar view at the air intake and gas outlet side at the same.

Fig. 3 is a vertical transverse sectional view on a medial line of the carbureter.

I Fig. 4 is a view similar to Fig. 3, illustrating another form of the invention.

Fig. 5 is atop plan view, partially in section, of the structure illustrated in Figs. 1, 2 and 3.

Fig. 6 is also a fragmentary elevation, s with parts of the needle valve-controlling mechanism'ina position. of adjustment to which the same may be moved when starting the motor with which the carburetor is associated.

' and a similar bottom 12, the top and bottom being held in position upon the body 10 by screws 13 or their equivalent. The body 10 is) provided with an air intake 14 and an explosive mixture outlet 15. The outlet 15 is in the form of a sleeve having a coupling flange 16 to permit the same to be connected to an explosive motor. llithin the outlet 15 is a throttle valve 17, preferably of the butterfly type, and the axis of this valve extends to the outside of the outlet 15, at which point it is provided with an operating arm 18. To this arm 18 is connected the usual actuating devices for manipulating the throttle.

Within the body 10 and at a point adjacentto the lower side of the outlet 15 is a partition 19,'rising from the central portion of which is a tubular guide 20. At one side of the body 10 and at a point below the partition 19 a fuel inlet 21 is provided, which inlet is surrounded by a screw-threaded boss 22, to which a feed pipe leading from the supply of the liquid fuel may be connected. It is proposed to rely on variable pressure conditions within the carbureter for feeding the liquid fuel to the same, as will be explained'more fully hereinafter, and. to prevent return of that portion of the fuel which remains within the carbureter when the operation of the motor has ceased, the feed line at a point between the supply and the 'carburetershouldbe provided with a check valve. The application of such a check 'valve will be obvious.

The present invention embodies and operates on the principles of a Venturi tube and it therefore includes a tapered throat for the passage of the air on its way to be mixedwith the liquid fuel. This construction is attained by means ofa movable air valve 23 which fits the bore of the body 10 and, is slidably mounted therein. The movable valve 23 is in the form of a cylindrical shell, the bore of which is tapered from. a point midway its ends to the ends of the shell, the tapering of the bore extending in opposite directions, asclearly illustrated. in Fig. The bore of the "valve 23 therefore flares outwardly toward the air intake 14 and inwardlytoward the outlet, 15. At the lower end of the movable valve 23 is arranged a disk 24 having a plurality of openings 25 therein to afi'ord communication between the bore of the valve and the lower wearer ceived by the tubular guide 20 and at its lower end is provided with a plunger or piston 29.

Arranged within the tubular stem 27 and I rising upwardly from the bottom 12 is a 76 tubular guide 30. The guide 30 is obviously a stationary element and the stem 27 is adapted to move along said guide as the valve 23 is operated in the manner hereinafter described. At the upper end of the guide 30 is arranged a. stationary air valve 31, said valve having a screw-threaded engagement 32 with the guide 30 and thereby being displaceable from said guide. The valve 31 serves the purpose of a cap for the guide 30 and thereby closes its upper end. The edges of the valve 31 are beveled to conform to the angle of the upper end of the flared bore of the valve 23, the flared bore, and the beveled edges cooperating to close the space within the throat and thereby cut off communication between the air intake 14 and the interior of the body 10 below the valve 31. The valve 31 is also provided at its lower end with an annular flange 33 arranged in spaced relation to the body portion of the valve and the sides of the latter are also provided with ports 34 which communicate with ports 35 formed in the sides of the guide 30. These ports 3t 100 and 35 permit the flow of the liquid fuel from the interior of the guide 30 to the interior of the body 10 and as'the fuel emerges through said ports it is brought into contact with theair passing between the edges 105,

of the valve 31 and the bore of the valve 23, when the latter is unseated.

The stationary valve 31 is also perforated to permit passage of a needle valve stem 36, the lower end of which is provided with 11 a. needle valve 37 which cooperates with a valve seat 38 screw-threaded within the guide 30. The stem 36 is connected to a screw 39 fitted within an inwardly ext-ending sleeve 40 carried by the top 11 of the 1 carbureter. This screw 39 has a milled head 41 at the exterior of the carbureter to permit manual adjustment of the needle valve stem 36 and thereby to regulate the relation of the needle valve 37 with respectto its seat 38. To hold the valve in its various 1 positions of adjustment, a spring detent 42 is arranged in juxtaposition to the milled head 41 and exerts its pressure against the serrated edges of said head to prevent rot-afor the passage of the fuel to dash-pot when such 30 is also provided upward movement pinion, it will be seen that the needle valve 37 may be caused to approach or recede from the seat 38. At the same time the rotation of the shaft 44 causes the pinion 43 to raise or lower the needle valve stem 36,the screw 39 and the pinion 43 acting in the capacity of a rack and gear. a

v Reference has been made to the plunger or piston 29 which is carried at the lower end of the stem 27. This" plunger is arranged to work between the partition 19 an the bottom 12, and the space between these parts therefore-constitutes a dash-pot. Within this dash-pot and interposed between the bottom 12' and the plunger 29 is a coile spring 45. This springis of sufiicient strength to maintain the plunger 29 in the upper end of the dash-pot when the engine is at rest and no suction is created to separate the valves 23 and 31. The limit of of the plunger 29 is such as not to close the port 21 and inasmuch as this port connects with the feed line leading from the liquid fuel supply it will be seen that the liquid fuel may pass through the port 21 and into the space between the parti- P and to provide the space below the plunger the latter has a port 47 controlledby a suitable check valve 48,- The urpose' of this valve 48 is to prevent return of the liquid fuel which has passed beneath the plunger 29. Communication between the dash-pot and the interior of the guide 30 is afforded by one or, more ports 49 arranged'at the lower end of said guide. With the fuel. present in the dash-pot the same will flow through he ports 49 to the interior of the guide 30, and on the initial starting of the engine the depression of the movable valve 23 will wardly, which in turn forces the liquid fuel into the guide 30 and upwardly therein to the valve seat 38, which it; needle valve 37 has'been prope ly adjusted in relation thereto. The bottom '12 has a screw-threaded boss 50 which may be closed by a suitable pet cock, said boss communicatin with theinterior of the guide 30 and permitting drainage of the latter and the is desired. The guide I with supplementary ports 51 so that when the plunger 29 is forced downwardly a sufficient distance to pass said .ports, the liquid fuel may fee directly from the port 21 through the ports 51 and into the guide '30 without passing into the space'beneath the plunger.

It is intended that the needle valve 37. shall move simultaneously with the throttle a proportionate flow of the be had with regard to the of the throttle valve. To

tion 19 and the plunger 29,

' liquid fuel may degree of opening this end the shaft has a connecting arm 52 attached to one pf shaft. This arm =The stud 57 is carried by d to a link 59, the' upper end of which is the stud 57 is likewise the motor. In other words,

force the plunger 29 down-' passes when the.

- valve 17.

of the throttle valve '17 hub on which its 'proj ecting ends.

One end of thisarm 52 is bifurcated as at 53 for receiving the shaft r 54 of the throttle valve, and by means of said bifurcation and a clamping screw 5 the arm 52 is held in fixed position on sai 52 is also provided with a slot 56 and working in said slot is a stud 57 which may be locked at different points in said slot 56 by means of a securing nut '58. i

and articulated provided with a similarly mounted stud 60, said stud 60 being received by a slot 61 screw 64 on the projecting end .of the shaft 44. .The stud 60, however, hasfree sliding movement in theslot 61, for a purpose to be presently explained, but inasmuch as the arm 62 is clamped upon the shaft 44 and as formed in an arm 62 provided with a bid furcated end 63 which isheld by a clamping held in fixed relation to the slotted arm 52, it will be apparent thatv as the arm 52v is swung in unison with the movement of the throttle valve 17, the arm 62 will likewise be moved and through the inion 43 and screw 39 the needle valve will be simultaneously opening orclosing movement valve.

The link 59 is adjusted to the arm 52 in accordance with the size of the motor and the volume of fuel which it is necessary to feed for the development of the power of it is obviously of the throttle It is also essential that there shall beanadequate supply of the fuel for starting the engine in its cold condition. There are times also when it is" desired to' speed up the engine more quickly than atothers, as for instance in speeding der certain conditions. To the present invention contemplates a manual adjustment pendently This is accomplished by an actuator cam-65 eccentrically mounted on the said shaft. ,The cam 65 has an arm 66 to which is connected an operating cable or cylinder motors 37 adjusted in relation to its seat 38 in proportion to the degree of an automobile un-, provide for this,

of the needle valve 37 indeof the opening of the throttle d shaft 44 and. independently movable of 1 wire 67 designed to lead to a distant point, a

such as the seat of the automobile, and to provide for the proper operation of the cable or wire it is incased in a tube 68 supported from the'body of the carbur'eter by a suitable bracket 69. The cam 65' has-a is loosely fitted an eccenthis strap 71 is also protric strap 71 and air in accordance .motor or the load imposed upon the motor.

tion hereinbefore recited.

vided with an arm 72 which receives the threaded end of the stud Mounted on the threaded end of the stud 60 is a spacing washer 73 against which the arm '72 is pressed by a nut- H. The eccentric strap 71 is held on the hub 70 by a clamping plate 75 which is secured to said hub by a '76 or its equivalent. When. the arm swung upon the shaft H by the operating cable or wire 67, as shown in Fig. 6, the cam will actuate the arm 72 through the hub and the strap 71 and the eccentric niot'ement of the cam will thereby shift the stud 60in the slot'til. The arm 62 is thereby swung and this movement of the arm rotates the shaft it which, through its connections with the valve stem 36, causes movement of the needle valve'37 away from its seat 38 and afiords flow of the necessary amount of the fuel to provide for'thestarting'of the motor in its cold speeding up the motor under the condi- The arm '72 also performs the function of shifting the stud 60 along the slot 61 and thereby varying the degree of throw of the arm 62 when the throttle valve 17 is opened or closed. This varying movement of the arm 62 will result in a varying movement of the needle valve 37 with a resultant 'arying feed of the fuel in proportionjto the movement of the throttle valve 1?.

Tn Fig. 4i is illustrated a slightly modifi'ed form of the invention. This form is designed to automatically proportion the flow of the fuel and the feeding of the with the speed of the T11 this form the body 10 of the carbureter is provided with a slot I? through which extends an arm 78 connected to the movable air .valve 23. A link 79 is pivotally connected to the arm 78 and also to an arm 80 connected to the shaft ett. Hence, as the movable valve 23 is operated, the arm 78. link 79 and arm 80 causea simultaneous rotation of the shaft -14; so that the needle valve is caused to approach or recede' from its seat to an extent proportionateto the speed of the motor. This is due to the fact that if the speed of the motor is decreased or increased the suction of the pistons will be decreased or increasedmnd the movement of the valve 23 will vary in accordance with the degree of this suction. The charge therefore is proportioned tothe speed of the motor and likewise the load. on the motor which, of course, varies the speed of the motor.

It is to be noted that the valve 23, wlien in its normal position of rest. projects across the air intake 1% substantially one-half the area of said intake, as seen in Figs. 2, 3 and 4. By reason of this restriction of the air intake t e suction 0n the fuel at the condition or for wearer ports 34 and 35 will be the greatest when the valves 23 and 31 are in contact with each other, or are in closed position, as shown in Fig. 3, and as they separate under the suction of the pistons, the effective area- 7( of the intake will become enlarged gradually but proportionately to the extent of opening of the valve 23 and also proportionatelyto the speed of the motor. This insures flow of the fuel at; the ports 3% and 35 when, starting the engine. The operation of the herein described car,- b'ureter is as follows: The fuel passes through the port- 21, through the valve controlled port 47 into the dash-pot and enters the. guide 30. The engine being at rest, the fuel willnot discharge to the interior of the body 10, but will remain within the guide 30. The needle valve 37 should be adjusted, of course, properly with relation to its seat. ()n the starting of the engine, a suction will be created within the carbureter. establishing a vacuum action and drawing the fuel upwardly in the guide 30. This vacuum action. however, will also draw themovable valve 23 downwardly and with its descent the plunger 29 will be forced downwardly against the tension .of the spring 45. This forcibly ejects a quantity of the fuel from the guide 30 through the ports 34 and 35, and as the movementof the valve 23 has provided a space between the same and the stationary valve 31, air also will be drawn through the intake 1-1 and into the interior of the body 10\to be mixed 1- withthe fuel discharged from the guide 30.

The intake 14 should be connected to a jacket about the exhaust of the engine so that the air entering through the intake '14- may be preheated. The reasons for this are 1 5 obviously to promote the vaporization of the fuel. As the engine'continues to operate,

the suction of its pistons will maintainthe flow of the. fuel, and this flow will be in w direct proportion to the extent that the 11 valve 37 is opened in relation to the degree of movement of the throttle valve 17. It will be understood that as the throttle valve 17' is operated to a greater or less extent, the needle valve 3? will also be'operated througlr the arm 52. the link. 59, the arm 62, theshaftat and the connections of the latter with the needle valve stem 36. Should it be desired to speed up the engine to a greater extent the operation of the. throttlel'T, as under normal conditions, the actuator cam 65'is manipulated in the manner hereinbefore described to increase the flow of the fuel as also described.

When the engine is stopped, it will be understood that the fuel remains in the guide 30, being held therein by the check valve in the feed line, and immediately upon the engine being than is rendered possible by ,120

again started, a supply of thetfuel isavailable at the ports 34 and 35 to provide for immediate discharge of the fuel at this point.

The space below the valves 23 and 31 and above the partition 19 constitutes the mixing chamber of the carbureter. WVith the valve 23 seated against the valve 31, the mixing chamber is effectually sealed against communication with the air intake 14. Should, therefore, back-firing occur, the pressure incident thereto will seat the valve 23 against valve 31 and prevent passage of the gases therethrough, so that fire risk is reduced to aminimum.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In a carbureter, the combination of a casing affording an air inlet passage and a suction passage, a chamber for liquid fuel and having a check controlled fuel inlet, a valve for regulating passage of liquid fuel between the chamber and suction passage, a piston operable in said chamber to increase the velocity of discharge through said valve independently of the valve adjustment, and means responsive to differences of'pressure between the inlet passage and suction passage for operating said piston.

2. In a carbureter, the combination of a casing affording an air inlet passage and a suction passage, a chamber for liquid fuel and having a fuel inlet, a valve for regulating passage of liquid fuel from said chamber to the suction passage, means operable in said chamber to increase the velocity of discharge through said valve independently of the valve adjustment, and means operable through flow of air from the inlet passage to'the suction passage for operating said means. v 4

3. In a carbureter the, combination, of a casing affording an inlet passage and a suc-' tion passage, a control member movable under difference of pressure between said passages for controlling communication therebetween, a chamber for liquid fuel, a piston operable therein, a connection between said piston and said control member whereby the movement of the latter is opposed by liquid in the chamber, means affording a valve port allowing communication between said chamber and the suction passage, and

a valve for controlling the effective area of said port; the movement of said control member under suction being effective to force liquid from the chamber through the valve port.

4. In a carbureter, the combination of a casing affording an inlet passage and a suction passage, a chamber for liquid fuel, a

tube extending into said chamber and-having communication therewith and With the suction passage, a valve in said tube for controlling passage of fuel from the chamber to the suction passage, a sleeve slidably guided on the tube, a piston operable by the sleeve in the chamber to force fuel therefrom through the tube, and a member controlling communication between the inlet and suction passages cooperating with said sleeve to move the iston.--

HARE K. TARKINGTON. \Vitnesses:

MILTON T. MILLER, VILLIAM N. CROMWELL.

Images