US2786659A - Carburetors, including an auxiliary starting device - Google Patents

Description

United States Patent CARBURETORS, INCLUDING AN AUXILIARY STARTINGZDEV'ICE Andrv Louis M'ennesson, Neuilly-sur-Seine, France, assignor to Solex S. A., Neuilly sur-Seine, France, a scietyof France Application September 10,1954, Serial No; 455,214

Claims priority, application Fra'uce- September 25, 1953 9 Claims. (Cl. 26-1-41) The present inventionfrelatesto. carburetors including an auxiliary starting device capable of delivering fuel toward the engine under the eifectof the suction existing in the induction pipe thereof downstream of the carburetor throttle, said' au xiliary device comprisng an independently operated distributing valve for controlling the delivery of fuel toward the downstream side of the throttle and; means operative by said distributing valve for slightly displacing said throttle in the opening direction from its maximum closing position when said distributing valve is moved into a position in which itdelivers fuel toward the downstream side ofthe throttle, whereby at leasta portion of the air to be mixed with the fuel supplied through said distributing valve is admitted through the passage thus afforded-by saidthrottle.

The object of the present invention is to improve the operation of such carburetors, whether their distributing valve is operated manually or automatically.

They consist chiefly in-providingsuch carburetors with means such that. the sectionoffiow afforded to. the fuel flowing. from the auxiliary starting device toward theengine induction pipe, downstream of the throttle, is controlled under the effect of the suction existing atthis place in said pipe, so as to be reduced when-saidsuction exceeds a predetermined value.

Preferredembodiments. of my invention will be hereinafter described with reference. tov the accompanying drawings, given-merely by way of example, and-in which:

Fig. 1 diagrammatically shows, partly in; elevational view. and partly. in sectional View, a carburetor made according to my. invention.

Fig, 1a is a; partial view showing a modification. Fig.v 2 is a partialsection-on the line IIII= of Fig; 1'.

Fig. 3. shows, similarly.- to Fig. l, but in a different relative position of theparts a portion of said carburetor.

Figs. 4 and 5 are views similar to Fig; 1. but correspondingto two difierentrelative:positionsofthe parts, theseviews showing the. distributing valve of. the carburetor.

OmFig. 1,. referenceqcharacter. 1- designates the body fi idfidz 0: he: Stream: ofi mixture: flowing from the; starting; carburetor: towardi the: induction pipe of the engine downstream off? that throttle: is: con-- troll-ail l 'zflfiifln ce qsvariationsrofi-tlreisuetion existingrin Im the: embodiment of 'ice z saidpipe at this place; in such manner asto be reduced when said suction exceeds a predetermined value.

Furthermore, preferably, supplementary means which may be combined with those just above mentioned arev provided so that the suction exerted on the fuel" supplied by the auxiliary starting carburetor is reduced when the suction existing in the inductionpipe, downstream. of the throttle, exceeds a predetermined' value, which may be the same as that just abjovementioned'.

in the embodiment of Fig, 1, the distributingvalveis constituted by a disc-ofisubstantially cylindrical shape 43.- pivotally mounted about an axis 44and 'kept by a spring, 45 in fluidtight contact. with a flat surface provided 0111 the body of the carburetor.

This disc 43is provided with a central recess. andwith three radial grooves 46 preferably at to eachzother, as shown in: dottedslines on. Figs. 1 4 andS.

An operating lever 47 iS.fiXedto disc- 43 whichaalso carries a cam 20; This cam v is adapted to cooperate as above indicated, with a lever 23 freely rotatable Orr-tho spindle of throttle S'and including an. abutment 25: upon which bears an adjustable screw 26 carried by a: lever 18 fixed on. the spindle of throttle 5- and; connected with the throttle spindle.

Three conduits or channels open into theflatsurface: which cooperates with disc 43'.

T he first one is the above mentioned downwardcon duit 14, the. opening of said conduit into said surface communicating, through a calibrated passage 48; (Fig.- 4.)" with a small recess 49 which-will be hereinafter more? explicitly referred to.

The second ofithese conduits,. designated by reference" numeral 50,. communicates with a cylindrical chamber 51, which. will alsobe more explicitly referred 1 toherein after.

The third of saidconduits, designated by reference character 52, communicates also with said chamber. 51 as it will be hereinafter explained.

Chamber 51 isformed, preferably vertically, in the body 1 ofthe carburetor;v Itsupper end communicates through a passage- 53-with-; the: main air intake of tlie carburetor and its lower end communicates with the engine inductionpipe,downstream:ofzthe'th-rottle; through a conduit 54, which. extendsmpwardlyin said chamber 51 in the form of a tube 55 provided at'its upper'end' with a large area aperture 56 and, its side wall, with a passage-57 of substantially smaller area. i

A. piston 58-is. slidable in chamber 51- above"tt1be" 55', and'this. piston is urged upwardly by a sprin'g' 59 of suitable characteristics as will beexplained hereinafter;

The whole is arranged 'insuch manner that-when said piston58-is in itslowermostposition, aslshown by Fig. 3, it closes the. large area passage 56: provided at the-top} of tube55while it opens. the outletof conduit 52- intochamber 51 thus causing: this outlet. to ccmmunicatd through passage 53 with the main air intake of the car buretor'.

On theother hand,',when piston 58 is pushed upwardlyby spring 59 (1Fig; l):so. ast-to'be brought in'to co'ntactwitli' its abutment: 60;. said; piston stops the outlet of conduit 52 and simultaneously opens: the largearea passage 56 of tube 55, thus connecting it with ccndt iit fll.

Conduits 14,: 50. and"52 open into the flat surface of the carburetor body, which cooperates with disc 43; in? such mannerthat each of these channels either be stopped by-disc 4301' on the contrary beplaced irrcbm: munication with one of the three radial grooves, 46 provided in disc 43; accordingto' the" position Qffsaid: disc.

Forinstance; in'Fi'g; l", disc43"isin' a posi'tionsucili that. tli'e thr'ee conduits 14-,"59 a'nd 5'2 communicate freely together through grooves 46 and the central recess of disc 43.

On the contrary, in Fig. 4, where disc 43 is shown as having been slightly rotated in the clockwise direction, conduit 14 is in communication with the corresponding radial groove of disc 43 only through the small area recess 49, whereas the communication between conduits 50 and 52 takes place only through a passage of smaller section.

Finally, in Fig. 5, the three conduits above referred to are fully separated from each other.

Of course, the openings of conduits 14, 50 and 52 into the flat surface of the carburetor body and/or the grooves of disc 43 are provided in such manner that, starting from the fully open position of the distributing valve (starting from cold), as shown by Fig. 1, when said distributing valve is gradually closedthe flow of sections supplied by the distributing valve for the three above mentioned channels also decrease gradually until they are fully stopped.

Cam 20 is arranged in such manner that when the distributing valve is in the fully opened position (Fig. l), throttle is slightly opened whereas when the distributing valve is being gradually closed, the throttle is also gradually returned (Fig. 4) to its idling rimming position (Fig. 5).

This device works in the following manner:

It is known that when the engine has to be started from cold it is necessary to obtain a very rich mixture whereas on the contrary this mixture must very quickly become leaner as soon as the engine has been started.

On the other hand, when the engine is running but before it has reached its normal temperature of operation, it is necessary to obtain, for all running conditions, a mixture which is slightly richer than that normally supplied by the normal jet systems of the carburetor.

These conditions can be complied with owing to the provision of piston 58 and of the distributing valve constituted by disc 43.

When starting from cold, the elements are in the relative positions shown by Fig. l. Lever 47 then causes the displacement of lever 23 by cam 20 to be maximum. This lever 23, which acts through its abutment 25 on screw 26, actuates lever 18 and throttle 5 to open it to a degree slightly greater than the normal opening for idling runmng.

The three radial grooves 46 connect together conduits 14, 50 and 52. Piston 53, which is pushed upwardly by a spring, afiords a free passage through tube 55 toward conduit 54.

When the engine is driven by the starter, there is produced in the induction pipe a suction the value of which determines the strength to be given to spring 59. This spring must be sufficiently strong to keep piston 55 in upper position despite the action of said suction thereof.

In these conditions, this suction, which is relatively low because of the small speed with which the engine is driven by the starter, sucks in fuel from well 11 through Elie orifices of tube 13 and through conduits 14, Si and As no air inflow is provided to weaken the suction exerted on the fuel in tube 13, I obtain a mixture as rich as it may be desired and the richness of which is determined by the choice of jet 12, of the calibrated air passage provided at the top of well 11 and of the orifices provided in tube 13.

As soon as the engine is running, its speed suddenly increases from 100/150 revolutions per minute to at least 700/800 revolutions, and consequently the suction in the induction pipe and in conduit 54 becomes much higher than when the engine was being driven by the starter.

The characteristics of spring 59 must be such that, in these conditions, piston 53 is then moved down by the suction existing in conduit 54 and closes the large area passage 56 provided at the top of tube 55, allowing fuel to pass only through calibrated hole 57 (Fig. 3).

Simultaneously, the opening of conduit 52 is cleared and air penetrates, under the effect of the suction, through conduit 53, conduit 52 and the radial grooves 46 of the distributing valve, this air being directed toward conduit 59. The suction which is exerted on the fuel in tube 13 is therefore considerably lowered.

Thus, whereas the section of the air passage supplied by the opening of throttle 5 remains unchanged, the section through. which fuel is allowed to pass and the suction exerted on this fuel are considerably reduced. 1 thus ob tain, as soon as the engine is running by itself, a considerable reduction of the richness of the mixtures, whereby it is possible to make use of extremely rich mixtures when the engine is being driven by the starter, while obtaining normal mixtures as soon as. the engine has been started and is running by itself.

As the engine is warming up, the driver is led to reduce the action of theauxiliary starting carburetor, chiefly in order to reduce the speed of the engine. This action is exerted either manually or automatically according as the construction of the apparatus may be, but the principle remains the same in both cases.

For instance, Fig. 4 shows an intermediate position of disc 43 between the maximum acting position (Fig. l) and the disconnecting position (Fig. 5). This Fig. 4 shows the three radial grooves of disc 43- connecting together only small sections of conduits 14, 50 and 52. it follows that the section of the passage of fuel is reduced while cam 20 enables lever 23 to move in anti-clockwise direction, which gradually returns throttle 5 into a position closer to idling running position.

Thus, by moving lever -47 in the clockwise direction, I obtain a reduction of the air fiow section, and at the same time a reduction of the fuel flow section, which contributes in reducing the speed of the engine.

Fig. 5 shows the disconnecting position for which none of the three conduits 14, 50 and 52 is in communication, whereas lever 23 is no longer in contact with cam 20 and occupies a fixed position corresponding to the idling running position of the throttle.

The system above described further has the following advantageous feature.

It is known that as long as disc 43 has not reached the disconnecting position thereof, when throttle 5 is opened by the throttle pedal acting upon lever 18, the suction exerted in conduit 5'4 drops Whereas, on the contrary, the main jet system starts feeding fuel into the carburetor.

The supplementary amount normally supplied by conduit 54 is no longer sufiicient, due to the reduction of the suction, to give the total mixture supplied by the carburetor a sufiicient richness and it is necessary, at this time, to have the amount of fuel supplied'by conduit 54 sub stantially increased.

This is what is obtained owing to the provision of piston 58 which, being no longer subjected to the action of a high suction, is returned by spring 59 against its abutment 60, thus clearing conduit 50 and stopping conduit 52.

In these conditions, the amount of fuel that passes through conduit 54 increases substantially and enriches the total mixture supplied by the carburetor.

I thus obtain, as long as the distributing valve is in operation, and for all running conditions, an increase of the richness of the mixture which is necessary for a good operation of said engine.

Fig. 1a shows a modified construction of the portion of the carburetor including piston 58 and the parts which cooperate therewith.

In the modified construction of Fig. 1a, tube 55 is dispensed with. Piston 58 has its open end turned downwardly instead of upwardly as in Fig. 1. The outer wall of this piston is provided with an annular groove in the bottom of which is provided a small hole 57a extending through the piston hole.

With this arrangement, when piston 58 is held in uppe positi-mn y spring .2i'fu lte rflow?directly-from;conduit? 9 n q-s on itr 5.4; (:whi corresp nds; toifuelzflowina: thr; h the large area; open 561 of tube55 in;the con: struction of. Eigg, 1), On thecontraty, when the suction increases; in; conduit; 54, piston; 5.8 movesdownfland; this direct large area: passage is replaced by hole ,57a; (cor-responding to holed-7 of; Fig. l): The, operationisithcrefore qu val nt,

In a; general manner,- While I; have-,in; theabove description, disclosed what I' de,em;to; be practical andeificient; embodiments: of my inventioni. i would be well understood that I donot; wishtobe; limited thereto; as there; might be; changes, made, in; the; arrangement, disposition and form of the parts withoutdeparting fromthe principle-Youth; present invention ascornpnehended within the sen e ofthe,accompanyingclaims.

' iSj V 1;. In, a carburetor. includingan induction pipe and a throttle in-saidginduction pipe, an'auxilia-ry starting device which-; compri ses, in-combination, a;conduit opening into said nduction pipe downstreamof-saidsthrottle, a source offue;l,-,a conduit leading from saidsource, a distributing valvefor co-ntrollingthe-lfiowof-fuelfrom said source to said induction pipe, said1valve being provided with a-passage arrangedto interconnectsaid two conduits for a given position of said valve,- meansoperatively connecting said; distributing valve with said throttle for opening said throttle-from' its maximum closing position in response to, the bringing of said valve into said position, and means responsive tovariations of the suction in said induction. pipe-downstream of said throttle, for throttling one of said, conduits for increases of said suction'above a predetermined:value.

- 2. In acarburetor including an induction pipe and a; throttle. in'said induction pipe,an auxiliary startingde:

vicewhich comprises, in combination, aconduit opening into-saidinduction pipeedownwstream of i said throttle, a so rceof; fuel, conduitleading from said source, adistributingvalve for controlling the flow of fuel from said source-to said inductionp ipe, said valve being provided with-a'passage arranged to interconnect said two conduits for a given position ofsaid valve, means operatively con: necting said distributingvalvewithsaid throttle for opening-saidthrottle from its maximum closing position in re-- sponse to the bringing of said valve into said position, and means; responsive to variations ofthe suction in said in.-

duction,pipedownstreain of said throttle, for throttlingsaid,first mentioned conduit for increases'of said-:suc tion above a predetermined value.

3. In a carburetor includingan induction pipe and a throttle in said induction pipe, an auxiliary starting evice which comprises; in combination, a conduit opening into said induction pipe downstream of said throttle, a source of ifuel, a conduit leading from said source, a distributing valve for controlling the flow of fuel from said source to said induction pipe, said valve. being provided with a passage arranged to interconnect said two conduits for a given position or" said valve,- means-operatively connecting said} distributingyalve with said throttlefor opening-said throttle; ro -n is maximum closing, position in responseto the bringing of said valve into said position, and a single means, responsive to variations of the suction of said induction pipe downstream of said throttle, for throttling said first mentioned conduit for increases of said suction above a predetermined value, and for reducing the total suction exerted on the stream of fuel controlled by said distributing valve for increases of said first mentioned suction above said predetermined value.

4. In a carburetor including a carburetor body provided with an air intake, an induction pipe and a throttle in said induction pipe, an auxiliary carburetor which comprises, in combination, a source of fuel, a conduit leading from said source, a cylindrical housing formed in said carburetor body and communicating at one end with said air intake, a conduit starting from the other end of said housing and. Qn ni giimo, saidsindi tiqt nin ad uns ea t. ensaidnht ttten massa ing into the cylindrica-l wal first mentioned end: thereof N i p mentionedi end;v distributing; valve, fpg; controlling. the, flower fuel from said sourcesto said induction pipe, said valve-being arrangedrtotconnect, fonaeg-ivempositio there of, both said; first mentioned conduit, and said first; men: domed-passage; with said secondm tinned passage, and slide valve means in' said housing, movable-in (response-to suction variations; in said second-mentioned conduit for. connecting,- said,s ec o-nd mentioned-passage with said second mentionedi conduih through ailarge area. section: of flow while closing; said; firstmentioned' passage. when said. suctionis low and connectingsaid seeondmentioned pas;- sage with said secondmentionedconduit throughsa small, area section of flow while, openingg s 'd'firstmentioned en said suctiontisiaboveva. given,value.v

5. In a carburetor including; a Carburetor body provided with an air intake, aminduction; pipe, and a throt tie in said-induction pipe an aux-iliary, carburetor which, comprises, in, combination, a sourc of, fue1,,a conduitleading from said source, a; cylindriealr housing; formed. in said carburetor body and communicating-at one endwith said air intake, a conduit. starting from the, otherr end of said housingandopeninginto: saidinduction-pipe, downstream of said throttle, twoipassages. in-said-carbu retor body openinginto, the cylindrieahwall of said hous.-. ing, one near the: first mentioned, end thereof the-other near the second mentioned" end, a; distributing; valve, for controlling the flow of fuel from said, source tosaidi; in duction pipe, said; valve'being; arranged to connect,'for a, given-position thereof, both saicLfi st mentioned conduit; andsaid first mentionedpassage ;with saidv second; men tionedjpassage, means operatively; connecting; saiddise tributing valve with saidthrottle; or opening saidtlirottler slightly from its maximum; closingposition nF-response to the bringing of'said valve: intogsaid positiomandsslide; valve means insaidhousing ,movablesinresponse to suction variations in saidsecond;mentioned conduit for-con: nectinggsaid second mentionedz p assage with said second mentioned conduit through a largeiarea section; of flow; while closing ysaid first mentioned-passage:whensaid suction is-low andconnecting said second mentioned pas:- sage with said second mentioned conduit through asmall; area section of flow while ope-nin said; first mentioned, passage when said'suction is above, 18':

6. In a carburetor including acarbluretorbodyprovided; with an air intake, aninduction pipe andra throttle in said! induction pipe, an auxiliarycarburfltor:which comprises,, in combination, a source of: fuel,, a; conduit leading from; said source, a cylindrical housingiormed in saidrcarbur retor body and communicating at one end with said air; intake, a conduit starting frommg: other end of. S id: housing and opening into said induction.pipeidownstreams of said throttle, two passages inrsaid5carburetor bodyopen:- ing into the cylindrical wall; of: said housing,,. one-. nea-r; the first mentioned endi'thereofithe other; near: the;s6,c+ 0nd mentioned end, a distributing valve: for; controlling the: flow of .fuel from s aid ;source;to said induction ,pipe; said valve being arranged to connect, for a given position thereof, both said first mentioned conduit and said first mentioned passage with said second mentioned passage, a tube forming an extension of said second mentioned conduit into said housing, said tube having its end located in said housing open and being provided in its side wall located in said housing with a hole of a section smaller than that of said open end, a piston slidable in said housing in the portion thereof beyond said tube, said piston having one end adapted to fit on said tube open end so as to stop it, said piston being adapted, when in the position where said end thereof is closing said tube open end, to uncover the opening of said first mentioned passage into said hole, and, when it is moved away from said position, to cover'said opening, and spring means hetween said piston and the second mentioned end of said casing for urging said piston away from said housing second mentioned end, said spring means being adjusted to oppose the effect of a low suction in said second mentioned conduit and to yield to a higher suction.

7. In a carburetor including a carburetor body provided with an air intake, an induction pipe and a throttle in said induction pipe, an auxiliary carburetor which comprises, in combination, a source of fuel, a conduit leading from said source, a cylindrical housing formed in said carburetor body and communicating at one end with said air intake, a conduit starting from the other end of said housing and opening into said induction pipe downstream of said throttle, two passages in said carburetor body opening into the cylindrical wall of said housing, one near the first mentioned end thereof the other near the second mentioned end, a distributing valve for con trolling the flow of fuel from said source to said induction pipe, said valve being arranged to connect, for a given position thereof, both said first mentioned conduit and said first mentioned passage with said second mentioned passage, means operatively connecting said distributing valve with said throttle for opening said throttle slightly from its maximum closing position in response to the bringing of said valve into said position, a tube forming an extension of said second mentioned conduit into said housing, said tube having its end located in said housing open and being provided in its side wall located in said housing with a hole of a section smaller than that of said open end, a piston slidable in said housing in the portion thereof beyond said tube, said piston having one end adapted to fit on said tube open end so as to stop it, said piston being adapted, when in the position where said end thereof is closing said tube open end, to uncover the opening of said first mentioned passage into said hole, and, when it is moved away from said position, to cover said opening, and spring means between said piston and the second mentioned end of said casing for urging said piston away from said housing second mentioned end, said spring means being adjusted to oppose the effect of a low suction in said second mentioned conduit and to yield to a higher suction.

8. In a carburetor including a carburetor body pro vided with an air intake, an induction pipe and a throttle in said induction pipe, an auxiliary carburetor which comprises, in combination, a source of fuel, a conduit leading from said source, a cylindrical housing normed in said carburetor body and communicating at one end with said air intake, a conduit starting from the other end of said housing and opening into said induction pipe downstream of said throttle, two passages in said carburetor body opening into the cylindrical wall of said housing, one near the first mentioned end thereof the other near the second mentioned end, a distributing valve for controlling the flow of fuel from said source to said induction pipe, said valve being arranged to connect, for a given position thereof, both said first mentioned conduit and said first mentioned passage with said second mentioned passage, a piston slidable in said housing, the end of said piston nearer to the second mentioned end of said housing being open, and the opposite end being closed, the cylindrical wall of said piston being provided with a small hole adapted to register with said second mentioned passage when said piston is in its end position toward said second mentioned end of said casing, the length of said piston being such that it then uncovers said first mentioned passage whereas it covers it when said piston is moved away from the second mentioned end of said housing, and spring means between said piston and the second mentioned end of said casing for urging said piston away from said housing second mentioned end, said spring means being adjusted to oppose the effect of a low suction in said second mentioned conduit and to yield to a higher suction.

9. in a carburetor including a carburetor body provided with an air intake, an induction pipe and a throttle in said induction pipe, an auxiliary carburetor which comprises, in combination, a source of fuel, a conduit leading from said source, a cylindrical housing formed in said carburetor body and communicating at one end with said air intake, a conduit starting from the other end of said housing and opening into said induction pipe downstream of said throttle, two passages in said carburetor body opening into the cylindrical wall of said housing, one near the first mentioned end thereof the other near the second mentioned end, a distributing valve for controlling the flow of fuel from said source to said induction pipe, said valve being arranged to connect, for a given position thereof, both said first mentioned conduit and said first mentioned passage with said second mentioned passage, means operatively connecting said distributing valve with said throttle for opening said throttle slightly from its maximum closing position in response to the bringing of said valve into said position, a piston slidable in said housing, the end of said piston nearer to the second mentioned end of said housing being open, and the opposite end being closed, the cylindrical Wall of said piston being provided with a small hole adapted to register with said second mentioned passage when said piston is in its end position toward said second mentioned end of said casing, the length of said piston being such that it then uncovers said first mentioned passage whereas it covers it when said piston is moved away from the second mentioned end of said housing, and spring means between said piston and the second mentioned end of said casing for urging said piston away from said housing second mentioned end, said spring means being adjusted to oppose the effect of a low suction in said second mentioned conduit and to yield to a higher suction.

References Cited in the file of this patent UNITED STATES PATENTS 1,898,958 Heitger Feb. 21, 1933 1,945,199 Mock et a1. Jan. 30, 1934 2,569,782 Sloane Oct. 2, 1951 2,621,911 Lindsteadt Dec. 16, 1952 FOREIGN PATENTS 397,073 Great Britain Aug. 17, 1933 832,810 Germany Feb. 28, 1952

Images