SE187913C1

SE187913C1 -

Info

Publication number: SE187913C1
Authority: SE
Publication date: 1963-01-01

Description

Uppfinnare: J Dolza, E Olson, Z Arkus-Dnntoy och J Zimmerman Prioritet begiird fran den 18 och 29 flint, 10 och 17 september 1956 (USA) Den foreliggande uppfinningen avser ett bransleinsprutningssystem for fOrbranningsmotorer med dels ett med bransleinsprutare forsett luftinloppssystem, dels ett huvudventuriror i luftinloppssystemet, dels en fore insprutarna belagen avtappningsventilkropp for avtappning av bransle, Aiken reglerar bransletillforseln till motorn i beroende av undertrycket i venturiroret pa sit salt att yid minskning av trycket i venturiroret bransletillforseln Okas, dels en anrikningsanordning med sadan verkan att nar motorn ir kall anrikningsanordningen Okar forhallandet mellan branslet och luften i den motorn tillforda bransleluftblandningen. Inventors: J Dolza, E Olson, Z Arkus-Dnntoy and J Zimmerman Priority requested from 18 and 29 flint, 10 and 17 September 1956 (USA). The present invention relates to a fuel injection system for internal combustion engines with a fuel inlet system provided with fuel injectors and a fuel injector system. main venturi in the air inlet system, partly a pre-injectors coated drain valve body for draining fuel, Aiken regulates the fuel supply to the engine in dependence on the negative pressure in the venturi on its salt to reduce the pressure in the venturi fuel supply Okas, partly an enrichment device with such an action the enrichment device Increases the ratio between the fuel and the air in the engine supplying the fuel-air mixture.

Uppfinningen avser att astadkomma ett brhnsleinsprutningssystem av detta slag, som är billigt att tillverka och sarskilt lampligt att anvandas vid masstillverkade forbranningsmotorer. Ett bransleinsprutningssystem enligt uppfinningen har ett minimiantal av rOrliga delar, vilka alla kunna framstallas, med de vanliga tillverkningstoleranserna, vilket gör systemet och de dari ingaende delarna lampligt for massframstallning. Da delarna i systemet ej beh8va vara utforda med precisionstoleranser erfordras ej nagon storre grad av individuell justering vid installningen och ej mer an den vanliga periodiska justeringen i fortsattningen. Trots denna forenkling har systemet formagan att noggrant portionera den mangd bransle, som motorn erfordrar under alla dess arbetsforhallanden, samt att dela branslemangden i lika delar och avgiva dem till cylindrarna, sit att motorn under alla forhallanden arbetar silsom den skall. The invention is intended to provide a fuel injection system of this kind which is inexpensive to manufacture and particularly suitable for use with mass-produced internal combustion engines. An industry injection system according to the invention has a minimum number of movable parts, all of which can be manufactured, with the usual manufacturing tolerances, which makes the system and the parts therein suitable for mass production. As the parts of the system do not have to be challenged with precision tolerances, no major degree of individual adjustment is required during installation and no more than the usual periodic adjustment in the continuation. Despite this simplification, the system has the ability to carefully portion the amount of fuel that the engine requires during all its working conditions, as well as to divide the amount of fuel into equal parts and deliver them to the cylinders, provided that the engine operates as it should under all conditions.

Uppfinningen kannetecknas darav, att anrikningsanordningen itr forsedd med dels ett hjalpventuriror med en ventilkropp for reglering av stromningen av luft genom hjalpventuriroret, dels ett termoelement for omstall ning av denna ventilkropp i beroende av motorns temperatur pa sit salt att ventilkroppen oppnar nar motorn Or kall for att medgiva stromning av luft genom hjalpventuriroret under alstrande av ett undertryck i detta, varjamte hjalpventuriroret är anslutet i serie till huvudventuriroret, sit att ett i detsamma alstrat undertryck forstarker verkan av det av huvudventuriroret alstrade undertrycket, vilket piverkar avtappningsventilkroppen och darmed 'Mar proportionen mellan branslet och luften. The invention can be characterized in that the enrichment device is provided with an auxiliary vent tube with a valve body for regulating the flow of air through the auxiliary vent tube, and a thermocouple for converting this valve body depending on the engine temperature on its salt that the valve body opens when the engine is cold. allow flow of air through the auxiliary venturi while generating a negative pressure therein, each auxiliary venturi being connected in series with the main venturi, provided that a negative pressure generated therein amplifies the effect of the negative pressure generated by the main venturi, which affects the drain valve body and the branch. the air.

Uppfinningen beskrives narmare i det fOljande med hanvisning till den bifogade ritningen. PE denna visar fig. 1 en vertikalsektion gen.om ett bransleinsprutningssystem enligt uppfinningen. Fig. 2 visor an sektion genom ett venturiinlopp hos det i fig. 1 visade systemet. Fig. 3 visar en sektion utmed linjen 10-10 i fig. 2. The invention is described in more detail below with reference to the accompanying drawing. In Fig. 1, Fig. 1 shows a vertical section through a fuel injection system according to the invention. Fig. 2 shows a section through a venturi inlet of the system shown in Fig. 1. Fig. 3 shows a section along the line 10-10 in Fig. 2.

Bransleinsprutningssystemet 100 har en bransletank 102, en luftregleranordning 104, och en bransleregleranordning 106, som I beroende air luftstrOmningen genom systemet reglerar bransletillforseln i proportion dartill. I systemet inga vidare anriktningsanordningar for att modifiera fOrhallandet melIan luften och branslet. Inloppet 108 har ett luftfilter 110 med en bojlig ledning 112, forbunden med inloppet 114 till ett venturiror 116 med ett strypstalle 113, ef ter vilket folj er en diffusorkanal 120. Ett spj fill 124 for reglering av luftstromningen och darmed motorns varvtal itr lampligen an ordnat efter strypstallet 118, raknat i stromningsriktningen, exempelvis i diffusorkanalen 120. Utloppet fran venturirOret 116 ar f8rbundet med inloppet till motorns inloppsfordelare. The fuel injection system 100 has a fuel tank 102, an air control device 104, and a fuel control device 106, which depending on the air flow through the system controls the fuel supply in proportion thereto. There are no further alignment devices in the system for modifying the relationship between the air and the industry. The inlet 108 has an air filter 110 with a flexible conduit 112, connected to the inlet 114 of a venturi 116 with a throttle stall 113, followed by a diffuser channel 120. A spindle 124 for regulating the air flow and thus the engine speed is suitably arranged. after the throttle body 118, traced in the direction of flow, for example in the diffuser channel 120. The outlet from the venturi 116 is connected to the inlet to the inlet distributor of the motor.

Inloppskanaler 132 aro anordnade i cylinderlocket 134, inloppsventilkroppar 136 styra instromningen av luft i cylindrarna 138. 2— — En matarpump 141 med relativt lagt tryck suger brfinsle fran tanken 102 och trycker det genom ett filter 142 in i en flottorkammare 144. En nottorreglerad nalventil 146 reglerar branslestromningen in i kammaren 144 och vidmakthaller en i huvudsak konstant bransleniva i denna for att sakerstalla en kontinuerlig tillforsel av bransle till motorn. En insprutningspump 148 suger branslet fran bottnen av flottorkammaren 144 och trycker branslet genom ledningen 150 in i insprutningssystemet. Dâ denna pump 148 ej reglerar branslemangden kan den vara av godtyckligt slag och drivas pa godtyekligt satt; en kugghjulspump, som drives av motorn, fir dock att foredraga, sá att pumpavgivningen star i viss relation till motorns varvtal och foljaktligen aven motorns behov av bransle. Normalt levererar pumpen 148 en storre volym och ett stone tryck an som maximalt erfordras av motorn; overskottet aterledes till flottorkammaren 144 medelst en avtappningsledning 152. Detta minskar belastningen pa matarpumpen 141, dá denna endast behover f6rse flottorkammaren 144 med den mangd bransle som verkligen forbrukas av motorn. Inlet ducts 132 are provided in the cylinder cover 134, inlet valve bodies 136 control the inflow of air into the cylinders 138. A relatively pumped feed pump 141 sucks fuel from the tank 102 and pushes it through a filter 142 into a float chamber 144. A groove-controlled needle valve 14 regulates the flow of fuel into the chamber 144 and maintains a substantially constant level of fuel therein in order to ensure a continuous supply of fuel to the engine. An injection pump 148 sucks the fuel from the bottom of the float chamber 144 and pushes the fuel through the line 150 into the injection system. Since this pump 148 does not regulate the amount of fuel, it can be of any kind and operated in any way; a gear pump, which is driven by the engine, is preferred, however, so that the pump delivery is in some relation to the engine speed and consequently also the engine's need for fuel. Normally, the pump 148 delivers a larger volume and a stone pressure that is maximally required by the motor; the excess is returned to the float chamber 144 by means of a drain line 152. This reduces the load on the feed pump 141, as this only needs to supply the float chamber 144 with the amount of fuel actually consumed by the engine.

Bransleregleranordningen har en membrankammare vid den ovre delen darav och en branslereglerande del vid den nedre delen darav. Den senare delen har ett inlopp 158, som är forbundet med insprutningspumpens 148 utlopp 150 medelst en ledning 160. Inloppet 158 liar ett andra filter 162 och en back.ventil 164. Sedan branslet passerat genom backventilen 164 inkommer det vid bottnen av en fordelarkammare 166 och strommar axiellt uppat genom denna. The fuel control device has a diaphragm chamber at the upper part thereof and a fuel control part at the lower part thereof. The latter part has an inlet 158, which is connected to the outlet 150 of the injection pump 148 by means of a line 160. The inlet 158 passes a second filter 162 and a non-return valve 164. After the fuel has passed through the non-return valve 164, it enters at the bottom of a distributor chamber 166 and flows axially upward through it.

Insprutningsledningar 168 utgâ fran kammaren 166 for fordelning av branslet till bransleinsprutare 170, som lampligen aro anordnade nara inloppsventilkropparna 136. En avtappningsventilkropp 172 ãr anordnad upptill i fordelarkammaren 166, sa. att Overskott av bransle, som inkommer i fordelarkammaren 166, avgar via avtappningsventilkroppen 172 for att Atervanda till flottorkammaren 144 Over avtappningsledningen 152. Mangden av branslet regleras genom laget av ventilkroppen 172, som reglerar den branslemangd som avtappas genom ledningen 152. Dâ det hydrauliska motstandet i insprutningsledningarna 168, insprutarna 170 etc. aro lika med motstandet i en enda insprutare, kommer brans1etrycket i fordelarkammaren 166 att svara mot mangden av det bransle som strommar till cylindrarna 138, och det uppat pa avtapp-ningsventilkroppen 172 verkande trycket kommer att svara mot mangden av det reglerade branslet. Injection lines 168 extend from the chamber 166 for distribution of the fuel to fuel injectors 170, which are suitably arranged near the inlet valve bodies 136. A drain valve body 172 is arranged at the top of the manifold chamber 166, said. that Excess fuel entering the manifold chamber 166 exits via the drain valve body 172 to return to the float chamber 144 via the drain line 152. The amount of fuel is regulated by the layer of the valve body 172 which regulates the amount of fuel drained through the line 152. Then the hydraulic resistance the injection lines 168, the injectors 170, etc. are equal to the resistance of a single injector, the industry pressure in the manifold chamber 166 will correspond to the amount of industry flowing to the cylinders 138, and the pressure acting on the drain valve body 172 will correspond to the amount of the regulated industry.

Membrankammaren har ett membran 174, som stracker sig tvars Over densamma under bildning av en ovre kammare 176 och en undre kammare 178. Membranet 174 är forbundet med ventilkroppen 172 medelst ett stang system 180 med en vertikal stang 182, som är forbunden med ledtappen 184 mellan en motviktsarm 186 och en havarm 188. Armen 186 ar svangbar omkring en fast axel 190, och armen 188 är svangbar omkring den nedre anden av en stodarm 192, som är fast anbragt pa en axel 194, vilken stracker sig genom den nedre kammaren. 178, sh att en mile 196 vid den nedre anden av armen 192 kan rulla pa en kamyta 198 hos havarmen 188. Laget av proportionsarmen kommer darfor att reglera stangsystemets utvaxlingsforhallande. The diaphragm chamber has a diaphragm 174 which extends transversely thereto to form an upper chamber 176 and a lower chamber 178. The diaphragm 174 is connected to the valve body 172 by a rod system 180 with a vertical rod 182 connected to the hinge pin 184 between a counterweight arm 186 and a sea arm 188. The arm 186 is pivotable about a fixed axis 190, and the arm 188 is pivotable about the lower end of a support arm 192 which is fixedly mounted on a shaft 194 which extends through the lower chamber. 178, so that a mile 196 at the lower end of the arm 192 can roll on a cam surface 198 of the sea arm 188. The layer of the proportion arm will therefore regulate the gear ratio of the rod system.

Kammaren 176 ovanfor membranet 174 ar forbunden med strypstallet 118 medelst en reglersignalledning 200, sa att nar luften strommar genom venturiroret 116 det undertryck, som alstras vid strypstallet 118 bringas att verka i den livre membrankammaren 176. Den nedre kammaren 178 är forbunden med ledningen 202 for att i kammaren vidmakthalla i huvudsak atmosfarstryck eller det tryck som Fader omedelbart fore venturiroret 116, i stromningsiiktningen raknat. Det uppkommer saledes en tryckskillnad Over membranet 174, och denna tryckskillnad ger en kraft vilken svarar mot mangden av den i motorn instrommande luften. The chamber 176 above the diaphragm 174 is connected to the throttle body 118 by means of a control signal line 200, so that when the air flows through the venturi 116 the negative pressure generated at the throttle body 118 is caused to act in the free diaphragm chamber 176. The lower chamber 178 is connected to the conduit 202 for to maintain in the chamber substantially atmospheric pressure or the pressure which Father immediately for the venturi 116, in the flow direction, has shaved. There is thus a pressure difference across the diaphragm 174, and this pressure difference gives a force which corresponds to the amount of air flowing into the engine.

Tva motsatta krafter komma salunda att verka pa ventilkroppen 172: en nedatriktad kraft som representerar mangden av den strOmmande luften och en uppatriktad kraft som representerar mangden av det strommande branslet. A-vtappningsventilkroppen 172 kommer att installa sig sa, att luft och brans-le stromma i ett visst forhallande till varandra, som beror pa svanglaget av stodarmen 192. DA motorn vanligen arbetar endast under delbelastning och sallan behover utveekla maximal effekt, Mlles under normala arbetsforhallanden stodarmen 192 lampligen i ett lage som ger en mager blandning for maximal ekonomi. Thus, two opposing forces will act on the valve body 172: a downward force representing the amount of flowing air and an upward force representing the amount of flowing fuel. The drain valve body 172 will adjust so that air and fuel flow in a certain relation to each other, which is due to the pivotal layer of the boom arm 192. The engine usually operates only under partial load and the shaft needs to exert maximum power, Mlles under normal working conditions the standing arm 192 suitably in a layer that provides a lean mixture for maximum economy.

Vid motorns startande är det onskvart att tillfora motorn en myeket fet blandning, som fix mera lattantandlig an den normala blandningen. For delta andamal tjanar en anrikningsanordning 204. Forhallandet mellan luften och branslet i en startblandning är ej sarskilt kritisk, och om endast blandningen ãr tillrackligt let kan den variera mom ett avsevart omrade. En sadan blandning fir emellertid avsevart fetare an vad som fir onskvart sedan motorn kommit igang och anvandes darfor endast under igangsattningen. Anrikningsanordningen 204 kan tillfora en extra branslemangd till fordelarkammaren 166, eller kan begransa den mangd bransle, som forbiledes fran fordelningskammaren 166 genom. ventilen 172 till returledningen 152. When starting the engine, it is unfortunate to add a very greasy mixture to the engine, which is more flattened than the normal mixture. For delta andamal, an enrichment device 204 serves. The ratio between the air and the fuel in a starting mixture is not particularly critical, and if only the mixture is sufficiently light, it can vary by a considerable range. However, such a mixture is considerably fatter than what has been desired since the engine was started and is therefore only used during start-up. The enrichment device 204 may supply an additional amount of fuel to the manifold chamber 166, or may limit the amount of fuel bypassed from the manifold chamber 166 through. valve 172 to return line 152.

Den visade anrikningsanordningen 204 anvander hada dessa utvagar. En anrikningsledning 206 är forbunden mellan utloppet fran filtret 142 och fordelarkammaren 166. Da. in- — —3 sprutningspumpen 148 kan vara svar att att verka med detsamma och/eller avger endast en ringa mangd bransle vid laga startvan/al, är det lampligt att anrikningsledningen ar anordnad att erhdlla bransle fran matarpumpens 141 utlopp, sa att den stora branslemangden darifran med fordel kan anvandas for detta andamal. En ventilkropp 208, som omstalles naedelst en solenoid 210, är anordnad i ledningen 206 for att reglera strainningen; ventilkroppen halles normalt i silt stangningslage for att hindra bransle fran att stromma in i eller ut ur fordelarkammaren 166. Solenoiden 210 med dess ankare 216 är anordnad i stromkretsen 212 till en elektrisk startmotor 214 far motorn, och nar startmotorn 214 startas kommer ankaret 216 att sdnka ventilkroppen 208, sa att bransle kan stromma fran matarpumpen 141 direkt in I fardelarkammaren 166. Ehuru det av matarpumpen 141 astadkomna trycket kan vara mycket lagt forhindras en trycksankning genom att branslet avgives till fordelarkammaren 166 efter backventilen 164, och pumpen 141 har tillräekligt tryck for att fordela tillrackliga mangder bransle till motorcylindrarna 138 fOr startande av motor. Ehuru denna branslemangd i stort sett hr oreglerad ger den en Hit antandbar blandning Dessutom, eller sasom ett alternativ till det beskrivna utforandet, kan solenoidankaret 216 dyen ha en arm 218 vid den ovre anden ddrav, som samtidigt ansattes mot och nedtrycker avtappningsventilkroppen 172, sã att denna stanger Oppningarna till returledningen 152 under starten. Alit bransle, som matas till fOrdelarkammaren 166, fOrdelas darfor till motorcylindrarna 138. Om insprutningspumpen 148 avger en tillracklig md.ngd bransle under star-ten kan anrikningen ske enbart genom att nedtrycka avtappningsventilkroppen 172. A andra sidan, om matarpumpen 141 avger tillrackligt med bransle kan detta avgivas direkt till f8rdelarkammaren 166 utan att avtappningsventilkroppen 172 stanger. The enrichment device 204 shown uses these scales. An enrichment line 206 is connected between the outlet of the filter 142 and the manifold chamber 166. Da. In- - —3 the injection pump 148 may be the answer that to operate immediately and / or emit only a small amount of fuel at the right starting time, it is appropriate that the enrichment line is arranged to receive fuel from the outlet of the feed pump 141, so that the large amount of fuel hence can be advantageously used for this purpose. A valve body 208, which is reshaped by a solenoid 210, is provided in the conduit 206 to regulate the straining; the valve body is normally held in silt closing position to prevent fuel from flowing into or out of the manifold chamber 166. The solenoid 210 with its armature 216 is arranged in the circuit 212 of an electric starter 214 in front of the engine, and when the starter 214 is started the armature 216 will sink valve body 208, so that fuel can flow from the feed pump 141 directly into the manifold chamber 166. Although the pressure provided by the feed pump 141 may be very low, a pressure drop is prevented by delivering the fuel to the manifold chamber 166 after the check valve 164, and the pump 141 having sufficient pressure to distribute sufficient amounts of fuel to the engine cylinders 138 to start the engine. Although this amount of industry is largely unregulated, it provides a heat flammable mixture. In addition, or as an alternative to the embodiment described, the solenoid anchor 216 may have an arm 218 at the upper second drive, which is simultaneously engaged against and depresses the drain valve body 172, so that this closes the openings to the return line 152 during start-up. All fuel fed to the manifold chamber 166 is therefore distributed to the engine cylinders 138. If the injection pump 148 delivers a sufficiently large amount of fuel during start-up, the enrichment can be effected only by depressing the drain valve body 172. On the other hand, the feed pump 141. this can be delivered directly to the manifold chamber 166 without the drain valve body 172 closing.

Sedan motorn startats och borjar arbeta men vid lag temperatur är det Onskvart att till-fora motor en nagot fetare blandning an som Sr onskvart vid normal motortemperatur. For detta andamal anvandes en anrikningsartordning 220, som verkar i beroende av motorns temperatur och ger den onskade anrikningen av branslet medan motor arbetar vid en temperatur under den normala drifttemperaturen. En sadan anrikning hstadkommes genom att modifiera styrkan av den signal, som erhalles fran strypstallet 118 genom signalledningen 200, nar heist motortemperaturen Jigger under det normala vardet. Anrikningsanordningen 220 har ett litet hjalpventuriror 222 i serie med huvudstrypstallet 118, sasom visat i fig. 1 och 2. Hjalpventuriroret 222 kan suga luft direkt frail atmosfaren eller frail ledningen 202, sa att det endast matas med luft, som passerat genom luftfiltret 110. Mangden av luft som strommar genom yenturiroret 222 regleras medelst en ventilkropp 224, som ãr anordnad mellan ledningen 202 och strypstallet 118. Ndr ventilkroppen 224 är i silt stangningslage strommar ingen luft frail ledningen: 202 och genom venturiroret 222. FOljaktligen kommer undertrycket vid strypstallet 118 att Over ledningen 200 verka i membrankammaren 154 utan na.gon and-ring, och ett normalt forhallande mellan luft och bransle erhalles. Nar ventilkroppen 224 oppnar kan emellertid luft stromma fran ledningen 202 genom venturiroret 222 och genom Oppningar i vaggen hos strypstallet 118 i huvudventuriroret 116. Denna luftstrom forstarker styrkan av signalen fran strypstallet 118 och kommer darfor att minska fOrhallandet mellan luften och branslet. Den grad i vilken signalen forstarkes och den grad i vii-ken forhallandet mellan luften och branslet minskas bestammes givetvis av den grad, i vilken ventilkroppen 224 oppnar. Laget av ventilkroppen 224 kan regleras medelst ett termoelement, sasom en bimetalltermostat 226, som är anordnad att omstalla ventilkroppen 224. Varmet for att paverka termostaten kan erkallas fran varmluft frhn ett varmeelement, som utvaxlar varme med motorn, eller fran ett elektriskt upphettningselement, som är anslutet till motors tandsystem. After the engine has been started and starts to work, but at a low temperature, it is Onskvart to feed the engine a slightly fatter mixture than Sr onskvart at normal engine temperature. For this purpose, an enrichment type arrangement 220 was used, which operates depending on the engine temperature and provides the desired enrichment of the fuel while the engine is operating at a temperature below the normal operating temperature. Such enrichment is accomplished by modifying the strength of the signal obtained from the throttle body 118 through the signal line 200 when the engine temperature is below the normal value. The enrichment device 220 has a small auxiliary venturi 222 in series with the main throttle body 118, as shown in Figs. 1 and 2. The auxiliary venturi 222 can suck air directly from the atmosphere or the frail conduit 202, so that it is fed only with air which has passed through the air filter 110. of air flowing through the yenturi tube 222 is regulated by means of a valve body 224, which is arranged between the line 202 and the throttle body 118. When the valve body 224 is in silt closing position, no air flows from the line: 202 and through the venturi tube 222. Consequently, the negative pressure at the throttle body 118 the conduit 200 operates in the membrane chamber 154 without any change, and a normal relationship between air and fuel is obtained. However, when the valve body 224 opens, air can flow from the conduit 202 through the venturi 222 and through openings in the cradle of the throttle body 118 in the main vent tube 116. This air flow enhances the strength of the signal from the throttle 118 and will therefore reduce the air to fuel relationship. The degree to which the signal is amplified and the degree to which the ratio between the air and the industry is reduced is of course determined by the degree to which the valve body 224 opens. The layer of the valve body 224 can be regulated by means of a thermocouple, such as a bimetallic thermostat 226, which is arranged to reposition the valve body 224. The heat for influencing the thermostat can be recovered from hot air from a heating element which exchanges heat with the motor, or from an electric heating element connected to the engine tooth system.

Ndr motorn befinner sig vid eller nara sin normala arbetstemperatur kommer termostaten 226 att omstalla ventilkroppen 224, sa att denna forhindrar stromning av luft genom venturirOret 222. Nhr motorn har normal arbetstemperatur kommer emellertid termostaten 226 att tillbakadraga ventilkroppen 224 i en grad som bestammes av motorns temperatur, och luft kommer att stromma frail ledningen 202 genom venturiroret 222 och till strypstallet 118. Undertrycket yid strypstallet 118 kommer shledes att i viss grad forstarkas beroende ph volymen av den luft, som strommar frail ledningen 202 genom venturiroret 222. Den sa erhallna modifierade vakuumsignalen frhu strypstallet 118 overfores genom signalledningen 200 till membrankammaren 176. Forhallandet mellan luften och branslet i den motorn tillforda bransleluftblandningen konamer darfor att anrikas i enlighet med den modifierade signalen. When the engine is at or near its normal operating temperature, the thermostat 226 will reposition the valve body 224 so that it prevents air from flowing through the venturi 222. However, when the engine is at normal operating temperature, the thermostat 226 will retract the valve body 224 to a degree determined by the engine temperature. , and air will flow from the conduit 202 through the venturi 222 and to the throttle 118. The negative pressure yid the throttle 118 will thus be somewhat increased depending on the volume of air flowing from the conduit 202 through the vent 222. The resulting modified vacuum signal the throttle body 118 is transmitted through the signal line 200 to the diaphragm chamber 176. The relationship between the air and the fuel in that engine supplying the fuel-air mixture may therefore be enriched in accordance with the modified signal.

Vid motors tomgang Or den genom venturi7 rOret 116 strommande luftmangden sà ringa att den erhallna signalen ej Or tillrackligt stark for att sakerstalla en noggrann reglering av branslemangden. Del är dessutom vid denna tomgang onskvart att tillfora en na.got rikare blandning an den som motor arbetar med under normala arbetsforhallanden. En tomgangsanrikningsanordning 228 kan anyandas for att farstarka signalen frail strypstallet 118 vid tomgang. Anordningen 228 har en liten oppning 230, som Or anordnad strax — — after spjallet 124, iströmningsriktthugen rak, nat, for att avkaima inloppsvakuumets Ett ton-igangsanrikningsror 232 med en reglerbar ventilnal 234 och en reglerventil 236 forbinder oppningen 230 med ledningen 200. Reglerventilen 236 pa'verkas i stangande riktning av en fjader men är forbunden med stangsystemet for spjfillet, sa att den oppnas endast nar spjallet 124 befinner sig i tomgangslaget eller i Overgangslaget frau tomgangslaget. Med andra ord, ledningen 200 är isolerad Fran tomgangsanrikningsanordningen 228 och paverkas_ ej av denna med undantag av under tom-gang. Nalventilen 234 ar inst011bar for reglering av den grad i vilken reglersignalstyrkan rnodifieras. At engine idle, the air flow flowing through the venturi 116 is so small that the signal obtained is not strong enough to ensure accurate control of the fuel flow. In addition, at this idle part it is undesirable to add a slightly richer mixture than that with which the engine works under normal working conditions. An idle enrichment device 228 may be used to amplify the signal from the throttle body 118 at idle. The device 228 has a small opening 230, which Or is arranged shortly after the damper 124, the flow direction straight, wet, to discharge the inlet vacuum A one-tone enrichment tube 232 with an adjustable valve needle 234 and a control valve 236 connects the opening 230 to the line 200. The control valve 236 is actuated in the rod direction by a spring but is connected to the rod system for the throttle so that it is opened only when the throttle 124 is in the idle stroke or in the transition stroke from the idle stroke. In other words, the conduit 200 is insulated from the idle enrichment device 228 and is not affected by it except during idle. The needle valve 234 is inst011bar for controlling the degree to which the control signal strength is modified.

Under tomgang ãr spjallet 124 stangt och reglerventilen 236 Oppen. Inloppsvakuumet, sasom modifierat av ventilnalen 234, kommer saledes att overforas till ledniugen 200 for att forstarka signalen fran strypstallet 118 och darigenom Oka tomgangsblandningens fethet. En. ventilskruv 238 i en ledning 240 for forbiledning av tomgangsl-uft forbi spjallet 121 kan anvandas for att reglera tomgangsluftvolymen och darmed motorns tomgangsvarvtal. During idling, the damper 124 is closed and the control valve 236 is open. The inlet vacuum, as modified by the valve needle 234, will thus be transmitted to the guide line 200 to amplify the signal from the throttle body 118 and thereby increase the fatness of the idle mixture. One. valve screw 238 in a line 240 for bypassing idle air past the damper 121 can be used to regulate the idle air volume and thus the engine idle speed.

For att fOrhindra en for plotslig minskning av vakutunet i membrankammaren 176 nar spjallet 124 oppnar fran tomgangslaget kan. ett (ej visat) kalibrerat strypstalle anordnas i roret 200, sa att dverforingen av en shdan vakuumandring till kammaren 176 fordrojes tillrackligt for att forhindra att motorn forlorar kraft innan strypstallet 116 aterigen Or I stand att reglera avgivningen av bransle till motorcylindrarna. To prevent a sudden decrease in the vacuum in the diaphragm chamber 176 when the damper 124 opens from the idle layer can. a calibrated throttle (not shown) is provided in the tube 200 so that the transmission of such a vacuum change to the chamber 176 is sufficiently delayed to prevent the engine from losing power before the throttle 116 is again able to control the delivery of fuel to the engine cylinders.

Sá snart spjallet 124 borjar oppna kommer motorvarvtalet att Oka nagot utover tomgangsvarvtalet och motorn borjar normalt att arbeta under belastning. For att under dessa forkallanden sakerstalla att motor. arbetar jamnt och utvecklar tillracklig kraft for att kunna arbete under belastning, Or det onskvart att tillfora en blandning som Or nagot rihare an den som tillfOres under normala forhallanden. Da ave. ett mindre oppnande av spjallet medfor en avsevard andring av inloppsvakuumet ger inloppsvakuumsignalen fran tomgangsoppningen 230 ej en helt tillfredsstallande signal under denn.a fas. Man kan darnir anordna en andra eller overgangsOppning 242 omedelbart framfor spjallet 124, i stromningsriktningen raknat, som är forbunden med tomgangsanrikningsledningen. 232 mellan reglerventilen 236 och ventilnalen 234. Denna andra oppning 242 Or sh anordnad att den befinner sig omedelbart vid omkretsen av spjallplattan 124. Luften kommer saledes att stromma genom den lilla oppningen mellan kanten ay plattan 124 och venturirorets 116 vagg samt tvars Over Oppningen 242. Den luft, sorn strommar genom denim begransade oppning, ger ett lokalt tryckfall eller en venturi effekt, .som avkannes av livergangsOppningen 242. Det lokala tryckfallet overfOres till regle, ringssignalledningen 206 ay tomgangsledningen. 232 for att fOrstarka signalen fran verituristrypstallet och darigenom alstra en fetare blandning vid overgangen fran tomgang. Nar spjallet 124 har oppnats forbi Oppningen 242 fOrefinnes ej langre det lokala tryckfallet och venturisignalen tager nu hand om hela regleringen. Det har emellertid befunnits onskvart att lata regleringsventilen 236 stangas sO snart spjallet 124 passerat overgangslaget och definitivt isolera venturisignalen fran verkningar, som annars skulle kunna fororsakas ay tomgangs- och overgangsmunstyckena 230 och 242 under motorns normala arbete. As soon as the damper 124 starts to open, the engine speed will increase slightly beyond the idle speed and the engine will normally start working under load. In order to avoid these engine during these summonses. works smoothly and develops sufficient force to be able to work under load, or it is unacceptable to add a mixture which is somewhat less than that which is supplied under normal conditions. Da ave. a minor opening of the damper due to a considerable change of the inlet vacuum does not give the inlet vacuum signal from the idle opening 230 a completely satisfactory signal during this phase. One can then arrange a second or transition opening 242 immediately in front of the damper 124, raked in the direction of flow, which is connected to the idle enrichment line. 232 between the control valve 236 and the valve needle 234. This second opening 242 is arranged immediately at the circumference of the throttle plate 124. The air will thus flow through the small opening between the edge of the plate 124 and the cradle of the venturi 116 and across the opening 242. The air flowing through the denim restricted opening produces a local pressure drop or venturi effect, which is sensed by the liver passage opening 242. The local pressure drop is transmitted to the control signal line 206 at the idle line. 232 to amplify the signal from the verituria staging and thereby produce a fatter mixture at the transition from idle. When the damper 124 has been reached past the opening 242, the local pressure drop no longer exists and the venturi signal now takes care of the entire regulation. However, it has been found unreasonable to let the control valve 236 close as soon as the damper 124 has passed the transition layer and definitively isolate the venturi signal from effects which might otherwise be caused by the idle and transition nozzles 230 and 242 during normal engine operation.

Det her befunnits att om i ett branslesystem av det beskrivna slaget insprutningsmunstyckena 170 Oro anordnade invid inloppsventilerna 136 och riktade mot dessa bildas endast en mycket liten fuktig yta i inloppsgrenroret. grund harav svarar motorn mycket snabbt pa en rorelse av gaspedalen. I sjalva verket arbetar den vanliga motorn bra utan nagon accelerationspump. Under vissa omstandigheter kan det emellertid vara Onskvart att anvanda en accelerationspump 260, som temporad 'Aar forhallandet av luft till branslet i blandningen nar spjallet 124 plotsligt oppnas for accelerering. Accelerationspumpen 260 har en kolv 262, som Or anordnad i en cylinder 264 mid den ena sidan av huset fOr regleringsanordningen Kolven 262 Or forbunden med spjallet 124 medelst ett fjaderpaverkat lank-system 266 med dodgangsrorelse. Bottnen av cylindern 264 Or forbunden direkt med fordelningskammaren 166 Over en backventil 268, som har ett mycket lhgt oppningstryck for att bransle skall kunna stromma fritt frail cylinder. 261 in i kammaren 166. Backventilen 268 forhindrar emellertid bakstromning av bransle frail kammaren 166. It has been found that if in an industry system of the type described, the injection nozzles 170 are arranged next to the inlet valves 136 and directed towards them, only a very small moist surface is formed in the inlet manifold. Due to this, the engine responds very quickly to a movement of the accelerator pedal. In fact, the standard engine works well without any acceleration pump. Under certain circumstances, however, it may be unwise to use an acceleration pump 260, which temporarily tempers the ratio of air to the fuel in the mixture when the damper 124 is suddenly opened for acceleration. The acceleration pump 260 has a piston 262, which is arranged in a cylinder 264 in the middle of one side of the housing of the control device. The bottom of the cylinder 264 is connected directly to the distribution chamber 166 via a non-return valve 268, which has a very low opening pressure so that fuel can flow freely from the cylinder. 261 into the chamber 166. However, the check valve 268 prevents backflow of fuel from the chamber 166.

Nar spjallet 124 stanges ror sig kolven 262 uppat i cylindern 264 mid ett insugningsslag och suger bransle fran branslespillkammaren. Nar spjallet 124 Oppnas kommer emellertid kolven 262 att normalt rora sig nedat. Denna nedatrorelse trycker en extra mangd bransle genom backventilen 268 in i fordelningskammaren 166. Det ar att marka, att under -vissa arbetsforhallanden Or bransletrycket i fordelningskammaren 166 mycket lagt och kan i sjalva verket overstiga det tryck, som astadkommes av accelerationspumpen 260. Accelerationspumpen 260 Or darfOr ej i stand att trycka in branslet i fordelningskammaren 166. Dodgangsmekanismen 266 medger darfor oppnande av spjallet 124 Oven om kolven 206 ej Mr sig. Om spjallet 124 halles tippet kommer branslet sa. smaningom att lacka bort och 161a en fjader 270 trycka kolven 262 till bottnen ay cylindern 264. When the damper 124 is closed, the piston 262 moves upwards in the cylinder 264 with an intake stroke and sucks fuel from the fuel spill chamber. However, when the damper 124 is opened, the piston 262 will normally move downwards. This downward pressure pushes an extra amount of fuel through the check valve 268 into the distribution chamber 166. It should be noted that under certain operating conditions the industry pressure in the distribution chamber 166 is very low and may in fact exceed the pressure provided by the acceleration pump 260. The acceleration pump 260 Or is therefore unable to push the fuel into the distribution chamber 166. The dodge access mechanism 266 therefore allows the opening of the damper 124. If the damper 124 is tipped, the industry will say so. gradually varnishing and 161a a spring 270 pushing the piston 262 to the bottom ay the cylinder 264.

Nar mo.torn har vent under belastning och spjallet 124 stanges kommer motorn att dri- — — vas pa grund av troghetskrafter. Under dessa forhallanden kommer det bransle, som forbrukas i motorn, ej att utfora nagot nyttigt arbete, utan gar forlorat, Em forbattring av bransleforbrukningen kan darfor astadkommas genom att eliminera bransletillforseln nar motorn drives pa detta satt. Vakuumet i inloppsgrenroret är mycket Mgt under dessa forhallanden och overskrider i sjalva verket vakuumet vid tomgang. Man kan darfor anvanda en bransleavstfingningsventil 272 for att avstanga bransletillforseln mar inloppsvakuumet overstiger tomgangsvakuumet. Ventilen 272 är anordnad i en forbiledning 274 fran inloppet 158 till branslereturledningen 152 och liar ett fjaderpaverkat membran 276, soin är forbundet med ventilen 272. Membranet 276 ãr anordnat att paverkas av inloppsvakuumet Over en ledning 280. Under normala arbetsforhallanden kommer fjadern 282 att halla ventilen 272 stangd, och bransleregleringen och fordelningen blir da den vanliga. Nar inloppsvakuumet overstiger det normala tomgangsvakuumet kommer emellertid det pa membranet 276 verlcande vakuumet att komprimera fjadern 282 och oppna ventilen 272. Bransle kommer nu att stromma fran branslematningsledningen till branslereturledningen 152 och darigenom ledas f8rbi fordelningskammaren 166. Da ventilen 272 är belfigen ovanfor backventilen 164, i stromningsriktningen raknat, blir trycket vid ventilen 272 relativt lagt. Backventilen 164 kommer dorfOr att forbli stangd. Harigenom elimineras all branslestromning till fordelningskammaren 166 tills inloppsvakuumet ãr det normala. Ventilen stanger da och bransle f5rdelas Ater till cylindrarna. When the motor has waited under load and the damper 124 is closed, the motor will be driven due to inertial forces. Under these conditions, the fuel consumed in the engine will not perform any useful work, but will be lost. Improving fuel consumption can therefore be achieved by eliminating the fuel supply when the engine is operated in this way. The vacuum in the inlet manifold is very Mgt under these conditions and in fact exceeds the vacuum at idle. One can therefore use a fuel shut-off valve 272 to shut off the fuel supply but the inlet vacuum exceeds the idle vacuum. The valve 272 is arranged in a bypass 274 from the inlet 158 to the fuel return line 152 and has a spring-actuated diaphragm 276, which is connected to the valve 272. The diaphragm 276 is arranged to be actuated by the inlet vacuum over a line 280. Under normal working conditions the spring 282 will slide 272 closed, and industry regulation and distribution will then become the norm. However, when the inlet vacuum exceeds the normal idle vacuum, the vacuum acting on the diaphragm 276 will compress the spring 282 and open the valve 272. Fuel will now flow from the fuel supply line to the fuel return line 152 and thereby be passed past the distribution chamber 27 in the valve 16. flow direction straightened, the pressure at valve 272 is relatively applied. The non-return valve 164 will therefore remain closed. This eliminates all industry flow to the distribution chamber 166 until the inlet vacuum is normal. The valve then closes and the fuel is distributed back to the cylinders.

Claims

Patent claim:

A fuel injection system for internal combustion engines with an air inlet system fitted with fuel injectors, a main vent vent (116) in the air inlet system, and a pre-injector-coated drain valve body (166, 172) for draining fuel, which regulates the fuel supply to the engine in the vent. pa sa. In order to reduce the pressure in the venturi, the fuel supply is increased, partly an enrichment device with such an effect that when the engine is cold the enrichment device Increases the ratio between the fuel and the air In that engine supply the fuel air mixture, characterized by the enrichment device a valve body (224) for regulating the flow of air through the auxiliary vent tube, and a thermocouple (226) for adjusting this valve body (224), depending on the temperature of the engine so salty that the valve body (224) opens to the engine. to allow flow of air through the auxiliary venturi (222). during the generation of a negative pressure therein, the auxiliary venturi (222) is not connected in series with the main vent (116), so that a negative generated therein amplifies the effect of the negative pressure generated by the main vent (116), which affects the drain valve body (224). hence 'Aar the proportion between the fuel air.

2. A system according to claim 1, characterized in that the thermocouple (226) is arranged to be heated by means of air heated by the engine.

3. A system according to claim 1, characterized in that the thermocouple (226) is arranged and is all heated by a heating element connected to the engine tooth system.

4. A system according to any one of claims 1-3, characterized in that the auxiliary venturi (222) is connected to the main vent (116) on such a salt that the air flowing through the auxiliary tube flows in through openings in the cradle of the main vent of the main vent (118). Request publications: Patents for Sweden 84 958; France 812 694, 907 51 2.