US1433545A - Carburetor - Google Patents

Description

P. P. GILLES.

CARBURETOR.

I APRLICAUON fILED AUGJ, l9l8. RENEWED MAR. 24. i922. 1,433,545. Patented oct 31,1922.

ETS-SHEET l VENTOR. B// 1 ATTORNEYS.

P. P. GILLES'.

CARBURETOR.

APFLICATlON FILED AUGJ, I9l8. RENEWED MAR. 24. |922.

Patented 00t- 31, 1922.

4 sHEETssHEE1 2.

INVENTOR. BZf/KQ' .5.

7 AToRNEYs'.

4 SHEETS--SHEET 3.

1 VENToR. '//fjv/ y ATTRNWS.

P. P. GILLES.

CARBURETOR.

APPLlc/Tlou msn Auw. 191B. nENEwED MAR. 24. 1922.

Patented Oct. 31, 1922..

P. P. GILLES.

CARBURETOR.

APPLICATION FILED AUGJ. 191s. nsuswrn MAR. 24. 1922.

4 SHEETS-SHEET 4- Patented Oct. 31, 1922.

A TTORNEYS.

Patented Oct. 3l 1922.

UNITED STATES PIERRE P. GILLES, 0F SPRINGFIELD7 MASSACHUSETTS.

CARBURETOR.

Application filed August 7, 1918, Serial No, 248,697. Renewed March 24, 1922.

To all fw hom t may conce/rn Be it known that I, Pinnen P. G1LLEs, born in Switzerland of German parentage, now believing myself to be a citizen of the Swiss Confederation, and having formally declared my intentions of becoming a citizen oi the United States of .America in confoi-mance with the United States immigra tion laws, and now residing at Springfield, in the county of Hampden and State of Massachusetts, United States of America, have invented certain new and useful Improvements in Carburetors, of which the following is a specification.

This invention relates to carburetors and more particularly to improvements which are designed to render carburetor-s more suitable 'tor use in vehicles which are driven aty high speeds.

It is now well-known that with a single spray nozzle the proportions of fuel and air in the fue] mixture Avary tor different engine speeds, the ratio ot' fuel to air being higher for high than for slow engine speeds. To remedy this difficulty, the compound nozzle has been proposed in which an additional nozzle is provided and arranged to deliver proportionately more Jfuel. at low than at high engine speeds. The two nozzles thus work in compensatory relation to the end that a substantially constant ratio between the constituents of the fuel mixture is approximated over a wide range of engine speeds.

lt has been my experience, however, that, while the compound nozzle Works satisfactorily 'or average speeds, as, for example, up to thirty-tive miles per hour or thereahouts in automobiles, it delivers an overrich mixture when the vehicle is run at the higher speeds as, for example, from forty to sixty miles per hour. This invention is concerned among other things with the provision ot means to improve the ratio oil the fuel constituents at high engine speeds and to make this improvement without altering the construction and design of the compound. nozzle which has proved `satisfactory for average engine speeds.

The invention has for an object to provide in combination with the compound'nozzle of a carburetor, a choke tube adjacent the nozzle, which tube is expansible from an opening of a predetermined size to another open*- ing oi inf-uletermined size throughout a limited range and is so constructed as to be Serial No. 546,491.

held normally to its smaller' and more restricted opening, but is movable when a predetermined engine speed is exceeded to enlarge the opening.

According to this object, after a certain engine speed has been exceeded and at about the time when the fuel mixture tends to become too rich, the choke tube expands, by the increased suction and increased velocity of the inrushing air, to diminish the suc tion so that less fuel is drawn from the compound nozzle. Thus, the expansible choke tube comes into play, when needed, as a supplementary regulating means for the fuel flow. which means combines with the compound nozzle by contributing to the same general result aimed at by the provision of the compound nozzle.

Another object of the invention is to provide in combination with a carburetor of the type described, means to automatically supply fuel to the carburetor by the suction produced in the intake pipe of the carbure tor. such means includingr a valve to open and close the fuel suction connection to the intake pipe and vary the degree of opening proportionately with the variations of the opening of the :intake pipe by the throttle, such means being particularly characterized by the provision of means which are operable independently of the position of the throttle to open the 'valve when, for any given throttle opening, the suction becomes insu'fiicient due to sl ackened engine speed.

According to this object when, for eXam ple` the engine lis running at high speed with a Jr'ull throttle opening and slackens in speed due to travel ot the automobile on a steep upgrade, more fuel may be supplied to the carburetor by providing an increased area upon which the suction, although decreased in degree, may act so that the supply or' fuel in the carburetor is maintained at the time when the maintenance of such supply is of the highest importance. ln this connection. it is to be noted that the expansible choke tube in addition to its primary func-tion may; under the described contingency, contract and thus aid in supplying increased fuel at this time while ordinarily it tends to reduce the fuel supplied to the engine. The improved valve arrangement for controlling the fuel supplied to the carburetor thus contributes to the work accomplished by the expansible choke tube.

Other objects and advantages will appear in the 'following description and will be pointed out in the appended claims.

The invention, in an embodiment at pres ent preferred, is disclosed for illustrative purposes in the accompanying drawings, in which- Fig. 1 is a top plan view of a carburetor' embodying the invention;

Fig. 2 is a sectional elevational view thereof taken on the line v2 2 of Fig. 1;

Fig. 3 is a cross-sectional view taken on the line of Fig. 1;

Fig. l is a sectional plan view taken on the line 1 11- of Fig. 3;

Fig. 5 is a sectional elevational view taken on the line 5-5 of Fig. il;

Fig. 6 is an enlarged sectional view of the compound nozzle of the carburetor;

Figp' is a sectional plan view taken on the line 7-7 of Fig. 6;

Fig. 8 is a fragmentary sectional plan view taken on the line 8-3 of Fig.

Fig. 9 isa fragmentary sectional eleva tional Aview raken on the line 9-9 of Fig. 1;

Fig.v 1() is a fragmentary sectional view which is taken similarly to Fig. 2 and shows a. modification in one feature of the invention; and

Fig. 11 is a cross-sectional view taken on the line 1,1-11 of Fig. 10.

Referring to these drawings, the carburetor casing, indicated generally by reference letter A, is formed with two main chambers 12 and 13, (Fig. e) arranged side by side in adjacent relation, and a substantially horizontally disposed air intake pipe 14- which as indicated in Fig. 2, passes through the `chamber 12. The casing A may be suitably made up, preferably for convenience in several sections held together by bolts 15 'l and 3), to provide leak-proof chambers, and the chamber fuel supply 13 is also made airtight by a suitable permanent cover member 16. rlhe chamber 12 is also closed at its upper end by a cover 1'? (Fig 2) pivoted to the cover member 1G and arranged to permit convenient access to the chamber 12. The latter is not sealed by cover 17, and air is purposely allowed to enter therein, as by a suitably screened opening 13 (Fig. 2).

Chamber 12 'constitutes the carburetor fuel chamber from which fuel is drawn into the suction pipe 14 through suitable atomizing devices. The atomizing devices are of the compound type, which involve main and compensating nozzles. Both these nozzles are contained in a sleeve 19 (F 2) which passes vertically downwardly through the pipe 141 and into a hollow tubular portion 2O of the casing 1l). The sleeve 19 has a lower portion 2l of reduced diameter, whereby a shoulder 22 is formed to seat on. a corresponding shoulder formed in the interior bore of member 2O and the sleeve 1 9 and its lower portion '21 closely fit the bore of member' 20 to prevent the passage of fuel therebetween. Fuel is supplied from chamber' 12 into the base of the tubular member 2O by way of passages 23 and 24 (Fig. 2). Fuel is also supplied from charmber 12 through an opening 25 (Fig. 9) regulable by a needle valve 26, into a passage 27 and thence into an lannular groove m member 20.

The main nozzle consists of a. tube 29 ing into sleeve 19 into cooperative relation with the upper end of passage 30. The tube 29 is necked down intermediate its ends to afford an annular passage 33 between it and the sleeve, and such passage lcomn'runicates by means of a hole 34 .in the reduced portion 2l, with the described groove 23 in member 20. The upper end of tube 29 is squared, as shown in Fig. 7, to afford openings 35 through which fuel from passage 33 may be drawn and delivered by way of openings 31 into pipe 14. The passage 33 constitutes the compensating nozzle of the carburetor.

Fixed at one end in the air intake pipe 1-1 is a choke tube 37 (Fig. 2) which, except for its fixed end, is composed of plurality of thin spring fingers 38. The describe( sleeve 19 passes loosely through two of these lingers and is disposed closely adjacent the restricted portion of the choke tube. 'lhe free ends of fingers 38 are flared outwardly as at 39, and their outer ends are normally slightly spaced .from the interior wall of pipe 14. The fingers 38 are so constructed that, with the degree of suction and the velocity of air obtaining` in pipe 1st on average engine speeds, they remain in the illustratedposit-ion to provide a choke of predetermined size for average running conditions. W hen, however, the degree of suction or the velocity of the inrushing air exceeds a predetermined value, the fingers 38 may yield to the limit prescribed by lthe abutment of' their outer ends with the interior wall of pipe l-l. Thus, a ""choke7 of greater opening, but still of predetermined size, is provided for the higher engine speeds.

The chamber 13 above described is a fuel supply chamber into which fuel ma v be drawn by suction, for subsequent deliverv by gravitv flow to the carburetor fuel cham-- ber 12. Referring to Fig. 5, a fuel inlet 4l() is provided in the upper portion of chamber 13, and such inlet is adapted to be connected to a low level fuel supply tank. Formed in an upwardly extending boss on cover plate 16 is a passage Ll1` the upper end thereof being enlarged to receive a ball valve 42 and to form a shoulder 43 on which the valve may seat. The upper end of passage 41 communicates with the atmosphere by way of openings 44 and below shoulder 43 the passage 41 is connected by passages 45 and 46 to the chamber 13, whereby, when ball 42 is held away trom its seat, as illustrated, air may enter the chamber 43. Slidable in passage 41 is a rod 47 which may lift ball 42 and hold it lifted as shown. On. rod. 47 and closely fitting passage 41 is a disc 48 which at all times prevents the passage of air from the upper to the lower portion of passage 41, but never closes communication between the upper portion and passage 45. A disc 49, also fixed on rod 47, may seat against the lower face of the cover to prevent com-` munication between chamber 13 and a pipe 50 which opens into passage 41 at such a point as to be always below the disc 48. Pipe 50 extends to the upper end oit a vertical passage 5l (Figs. 2 and 3), and such passage may communicate with the air intake pipe 14 in a manner to be later described in. detail.

lt will be seen that, with the parts in the relative positions illustrated in 5, air may enter chamber 13 while communication between the lat-ter and pipe 14 is prevented. The rod 47, however, may be lowered to a limited extent to allow ball 42 to seat on shoulder 43, and such niovement olt the rod. will carry disc 49 away from its seat, whereby pipe 14 may communicate with chamber 13 and communication between the latter and the atmosphere is prevented. The rod 47 is arranged to be moved sha rplv 'from one position to another by mechanism operated from a float 52 in chamber 13. Thus a pair o1 spaced arms 53 pivoted at 54 to cover plate 16 are pivotally connected to a rod upstandinf;v trom float 52. second pair ol spaced arms .'36 are loosely7 mounted on pivot 54 and extend toward the disc 49 and terminate with rounded ends` which ride in a .:ircumierential groove 57 Jformed in the disc. A spring 58 connects the opposite ends of each pair of arms 53 and 56. Thus. when the fuel in chamber 13 lalls to a predetermined level. the lowering of float 52 gradually draws arms 53 downwardly, and, as soon as the spring 58 crosses tothe lower side ot' pivot 54,` it sharply draws down arms 56 and thus rod 47 to the limit defined by the abutment of the rod and a ledge 59 on casing .f\ Fig. 5)` Similarly when the fuel in chamber 13 rises to a predetermined level, the 'raising of float 52 gradually raises arms 53 and, as soon as spring 58 crosses to the upper side of pivot 54` it sharply raises arms 56 and thus rod 47. Thus, the cham-4 ber 13 may alternately b e connected tothe atmosphere and the air intake pipe 14.

The chambers 12 and 13 are provided near their lower portions with openings 60 and 61, respectively which open into a passage 62 formed on the outer portion of the casing by a removable dish-shaped plate 63, all as shown in Fig. 4. Communication between the chamber 13 and passage 62 is cont-rolled by a check valve 64 which opens into the passage 62, as best shown in Fig. 5.

Referring now to Fig. 2, the described suction passage 51 intersects the air intake pipe 14, but the lower portion of the passage is made of reduced diameter' to receive and guide a squared stem 66 of a valve 67 which is adapted to seat against a shoulder 65 formed in passage 51 to prevent communication between the pipes 14 and 50. lNhen valve 67 is raised from its seat, communica tion between pipes 14 and 50 is permitted by way of the spaces between the squared shank 66 and the circular wall of the passage 51. The head of valve 67 is similarly squared, as indicated, tor a like purpose. The valve stem 66 is adapted to be lifted by a cam 68 formed on a throttle valve 69, which is arranged in pipe 14 and adapted to vary the effective opening thereof. Valve 69is oscillatable by a lever 69 (Figs. 1 and 3) in the usual manner. The cam 68 is constructed to move valve 67 as the throttle valve 69 is moved for the purpose of varying t-he effective opening of passage 51 proportionately with the variations in the effective opening ot pipe 14 by the throttle valve.

The 'face of' cam 68 consists of a curved spring which. is secured at one end to the Y of the spring are also spaced trom the cam, but by progressively decreasingr distances. The valve stem 66 is held to the cam, or more properly the spring 70, by suction, and the spring is made of such strength that it will be compressed by stem 66, as throttle valve 69 is turned, under the degrees of suc tion ordinarily obtaining in the intake pipe 14. Normally then the spring 70 acts merely as a facing for the cam 68, but it may, when the suction in. pipe 14 falls below a given degree, spring away trom the cam, as into the illustrated position. and thereby cause an additional litt of stem 66.

The essential feature of the valve construction described is the provision ot a re silient device between the cam 68 and valve 67, and it matters little just where such device is interposed. Thus, as shown in Fig. 10, the valve 67 may have a round stem 71 telescoped into and slidable relatively to, a hollow stem. 7 2, the end of which is arranged to bear on cam 68. The outer portion of stem 72 is of generally square lo intothe illustrated position.

50 llow through the passage construction (Fig. ill) for the same reason set :l'orth in connection with the valve stem tiGalreacy described. ifi spring 'Z3 stem 72 tends to lift stem 7l, but in normal operation held compressed due to 'the tgreater pressure acting` on the head of valve 67 than on stem 72. llilhen, however, the suction in pipe le falls below a predetermined degree, the si ring may litt stem 7l pin Tel, passing diametrically through stem 7l, has its ends disposed in slots 75 in the wall oitl stem 72, so that the degree or' movement between stems 7l and 72 is limited by the l confines of slots The valve 6i' is also made to periform another 'function lleil'erring` to Fig. 2, above valve 6T, an, annular ringu 76 is liXed in passage 5l, and the head of valve 67 may engage ring' 76, il: the valve 67 is moved beyond the limits prescribed by the throw or' cam 68 and the added increment of move ment which may occur by reason oit the spring; 7() or spring` 73. Thus, valve 67 may cooperate with ring/j 76 as a seat to prevent communication between pipes la and 50. rl`hus, upon baclliring, the excessive pressure in pipe lll; will torce valve 67 upwardly into engagement with ring;` T6, and

this result is Jarticularl' desirable here l Y l is drawn into chamber 1.3 by the suction produced in pipe la, which effective upon the chamber when valves 6'? and rLl-9 are open, by way olf' the passages Lil, 5U, and soon as the iiuel in chamber i3 reaches a pre- 40 determined level, valve 414.9 is closed by the rising of float 52 to prevent ilurther exhaustion or chamber 13, and the latter is then connected to the atmosphere by way oi passages l and iti and that portion of passage above disc e8, the ball l2 having,` been lifted free from its seat simultaneously with the closing' oit valve all. rlhe fuel in chamber lf2 is maintained. at the same level as that in chamber' 13 by gravity 62, the check valve @il preventing return flow. The rate at which fuelis drawn into chamber 13 is automatically controlled by the valve 67 which varies the area available for suction to act 55 on the chamber in rproportion to the variaof the engine slaclrens materially, the suction may decrease to such a degree that fuel is drawn into chamber 13 at an insu'llicient rate. At such times, namely, whenever 'the force acting` to hold the valve stem 66 against cam 68 becomes less than that of f4 i ,grasas springi- 70, the latter lilts valve 67 and thus increases the port area through which the air from the chamber lil is drawn, and this increase in port increases the rate oi flow ot fuel into chamber lll. Thus, when the carburetor is used on an automobile and the speed ci the latter even with a lull throttle opening slacltens, as on a grade, the springl0 or 73 acts and allows i'uel to be fed to chamber 13 at an increased httpl to compensate for increased. liow from chainber l2 through the atomizing devices.

rlhe high speed and compensating nozzles work in compensatory relation in the linown way so that under @Nera-ge conditions ol:l running, the ratio oil luel to air is maintained substantially constant. @n the very high speeds, however, the fuel mixture tends to become rich due to the high degree oit suction created in pipe llla't high engine speeds. ritter the suction in pipe 14; eX- ceeds a predetermined degree, the flexible blades are forced outwardly by the force of the inrushing air on their 'flared ends 39 with the result that the area. of the choke tube is increased, and such increased-area naturally decreases the velocity of the air adjacent `the exit or the nozzles and. thus diminishes the flow.

rlhe flexible choke tube also may func tion at times when the suction in pipe lilbecomes insu'llicient to draw suflicient fuel trom the nozzles to supply the needs ol the engine. rllhus, il the carburetor is usedv on an automobile and the` latter is travelling; at higzjh speed with a full throttle opeuinir. a slacliening oit engine speed due to the en? counteringl ol a grade will cause a decrease in suction, and the llexible blades 38, havingl previously been in expanded position due to high speed operation as described., will spring' into the illustrated position and, by restricting the pipe 1.4.-, cause increased suction and increased flow ol iliuel from the nozzles. The flexible choke tube and springs 70 or 73 thus contribute to the saine use'l'nl end, the latter providing; lor increased iieeding of luel into the fuel supply chamber 13 to replace the fuel drawn at an increased rate :trom chamber l2 by reason of the operation ol the flexible cholre tube in the described manner.

The texible choke tube thus possesses all the usual advantages ci the known variable choke tubes and in addition has an important primary advantage not` obtained with the usual variable choke tubes. That is to sf'iy.` the cholre tube in addition to its known functions combines with the main and compensating nozzles to improve and supplenient the proportioning oi the ingredients oi the ''uel mixture. nlhe present llexible choke tube is to be distinguished from the usual variable choke tube in that it is arranged to come into play only when the l. Ol)

velocity of the inrushing air has rear-,hed a predetermined value. It comes into play only at high speed and after the compound nozzle arrangement tails to satisfactorily regulate the proportions ot the constituents ot the fuel mixture. At all other timesand for average engine speeds, it provides a restriction ot pipe la to predetermined area and is movable at high speeds to a definite limited degree to provide a larger restriction of the pipe but still one of' predetermined area.

The invention has been disclosed herein, in an embodiment at present preferred, for the purposes ot illustration, but the scope of the invention is to be defined by the appended claims rather than by the Yforegoing description.

What I claim isl. In a carburetor, an air intake pipe adapted for connection to suction means, a fuel supply chamber adapted Aior connection to a low level iluel tank, means to deliver fuel from said chamber to the intake pipe, a passage coin'iectingthe latter to said charnber, whereby :fuel from the low level tank may be drawn by suction to said chamber, a throttle to vary the effective opening of' the intake pipe, a valve in said passage operable to vary the effective opening thereof pro-` portionately with the variations or said ine take passage by the throttle, and means op erable for any given position ot the throttle to impart an additional movement to said valve when the suction in said pipe diminishes to a predetermined degree.

2. In a carburetor, an air intake pipe adapted for connection to suction means, a fuel supply chamber adapted for connection to a low level vfuel tank, means to deliver fuel from said chamber to the intake pipe, a passage connecting the latter to said chamber, whereby Jfuel from the low level tank may be drawn by suction to said chamber, a throttle to vary the effective opening of the intake pipe, a valve in said passage operable to vary the effective opening thereof proportionately With the variations oit said intake passage by the throttle. and resilient means operable for any given position of the throttle to impart an additional movement to said valve when the suction in said pipe diminishes to a predetermined degree.

In a carburetor, a suction passage, a valve controlling said passage and normally movable toward closed position by the torce due to suction, and means operable to open said valve against the force due to suction. including means operable when the force due to suction decreases to a predetermined degree to move said valve beyond the position to which it is moved by the first-named means.

4. In a carburetor, an. air intake pipe adapted for connection to suction means, a throttle to vary the effective opening of said pipe, a passage communicating with the latter and to which suction is to be applied for fuel feeding purposes, a valve movable by the throttle to vary the effective opening of the passage, and resilient means between the valve and throttle operable When the suction in the intake pipe falls below a given degree for any given position of the throttle to impart an additional increment of movement to said valve.

5. In a carburetor, an air intake pipe adapted for connection to suction means, a fuel supply chamber into which fuel may be drawn by suction, means to supply fuel from the chamber to said. intake pipe, a suction passage between the chamber and intake pipe, spaced seats provided in said passage, and a valve normally cooperating with one seat to vary the effective opening of the passage and operable when the pressure in the intake pipe exceeds that in said passage to cooperate with the other seat and close the passage.

PIER-RE I. GILLES.

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