EP0020249A1 - Injection pump for internal-combustion engine - Google Patents

Injection pump for internal-combustion engine Download PDF

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Publication number
EP0020249A1
EP0020249A1 EP80400720A EP80400720A EP0020249A1 EP 0020249 A1 EP0020249 A1 EP 0020249A1 EP 80400720 A EP80400720 A EP 80400720A EP 80400720 A EP80400720 A EP 80400720A EP 0020249 A1 EP0020249 A1 EP 0020249A1
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EP
European Patent Office
Prior art keywords
piston
fuel
groove
chamber
delivery
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP80400720A
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German (de)
French (fr)
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EP0020249B1 (en
Inventor
Dirk Bastenhof
Roger Brisson
Claude Bonniot
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
MAN Energy Solutions France SAS
Original Assignee
Societe dEtudes de Machines Thermiques SEMT SA
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Priority claimed from FR7913486A external-priority patent/FR2457987A1/en
Application filed by Societe dEtudes de Machines Thermiques SEMT SA filed Critical Societe dEtudes de Machines Thermiques SEMT SA
Publication of EP0020249A1 publication Critical patent/EP0020249A1/en
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Publication of EP0020249B1 publication Critical patent/EP0020249B1/en
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M45/00—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship
    • F02M45/02—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts
    • F02M45/04—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts with a small initial part, e.g. initial part for partial load and initial and main part for full load
    • F02M45/06—Pumps peculiar thereto
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M45/00—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship
    • F02M45/02—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts
    • F02M45/04—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts with a small initial part, e.g. initial part for partial load and initial and main part for full load
    • F02M45/06—Pumps peculiar thereto
    • F02M45/066—Having specially arranged spill port and spill contour on the piston
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
    • F02M59/20—Varying fuel delivery in quantity or timing
    • F02M59/22—Varying quantity or timing by adjusting cylinder-head space

Definitions

  • the invention relates to an injection pump for injecting fuel into a cylinder of an internal combustion engine.
  • the invention particularly relates to an injection pump comprising a fuel receiving chamber defined in a cylindrical body, and variable in volume by the movement in this body, of a piston, according to an alternating back and forth movement , between a top dead center position and a bottom dead center position, this chamber being provided with at least one fuel inlet orifice, connected to a source of fuel of relatively low pressure and closable during the movement of said piston from its bottom dead center position to its top dead center position, to allow fuel to be discharged from said chamber to an injector associated with an engine cylinder, and the piston comprising at least one helical ramp at its periphery , which results in an axial groove and a circular groove connected by said axial groove inside said receiving chamber.
  • the known injection pumps of this structure have the disadvantage that the quantity of fuel injected into a cylinder, before ignition, can become relatively large in the event of a long ignition delay caused by too cold air or poor quality fuel.
  • ignition finally occurs a large amount of fuel ignites, which results in a sharp increase in pressure inside the combustion chamber causing great stresses in the component parts of the engine, such as the jacket, in the shaft bearings, sealing problems, for example at the head gasket, and noise.
  • the object of the invention is to propose an injection pump which makes it possible to carry out the pre-injection by means of an appropriate configuration, of the injection pump of the type described above.
  • the piston of the injection pump comprises a passage opening at one end into said fuel receiving chamber and capable of coming into communication, through its other end, with at least one channel opening into space inside the body coming from said fuel source, to interrupt at a predetermined time and for a predetermined period the delivery of fuel from said chamber to The injector during the displacement of the piston in the direction of its top dead center, the first delivery phase allowing a pre-injection of fuel into said cylinder and the second delivery phase ensuring a main injection.
  • the piston comprises below said first groove a second peripheral groove communicating with the first groove
  • the body of the injection pump comprises at least one aforementioned inlet channel, located below inlet orifices and closable by the peripheral surface of the piston, the inlet channel and said second groove being arranged so that the groove is capable of coming opposite said channel at a predetermined instant after the obturation of the orifices arrival by said piston, during the displacement displacement of the latter in the direction of its top dead center.
  • the injection pump according to the invention further comprises a fuel accumulator device allowing a variation in the quantity of pre-injection fuel without influencing the start of the main injection.
  • Figures 1 to 4 are longitudinal sectional views of a first embodiment of an injection pump according to the invention and illustrate specific steps in the operation of the pump;
  • Figure 5 is a sectional view along line V-V of Figure 2;
  • FIG. 6 illustrates the fuel delivery phases out of the injection pump chamber, as a function of the position of the piston of the engine cylinder, expressed in angular position of the crankshaft;
  • Figure 7 is a longitudinal sectional view of a second embodiment of an injection pump according to the invention;
  • Figure 8 is a sectional view along line VIII-VIII of Figure 7;
  • Figure 9 shows in a sectional view and schematically the accumulator device according to the invention, and
  • Figures 10 and 11 illustrate two concrete embodiments of an accumulator according to the invention.
  • the injection pump shown in Figures 1 to 5 comprises a cylindrical body 1 and a piston 2 movably mounted in this body 1 in a reciprocating rectilinear reciprocating movement, between a position of bottom dead center and a position of top dead center, under the effect of a control cam (not shown) secured to a shaft driven by the motor.
  • a fuel intake chamber 3 into which open fuel inlet orifices 4. These orifices are located at a level such that they allow the filling of the chamber 3 by the fuel, when the piston occupies its bottom dead center position.
  • a fuel delivery orifice in the direction of arrow F1, towards an injector associated with a cylinder of an internal combustion engine. This discharge orifice can be closed off by a discharge member, in a manner known per se.
  • the piston 2 has a first circular groove 5 delimited at its lower part by a straight edge 6 and at its upper part by a helical edge 7 forming a helical ramp and ending in a groove 8 which extends parallel to the axis of the piston .
  • This groove establishes permanent communication between the inlet chamber 3 and the groove 5.
  • the piston 2 is provided with a second circular groove 9, limited, in the example shown, above by a straight edge 10 and below by a straight edge 11.
  • This second groove 9 communicates with the first groove 5 through axial passages, formed in the example represented by two flats 12 formed on the flange 13 which is delimited between the two grooves 5 and 9.
  • the edges 6, 7, 10 and 11 each have a sharp angle of 90 °.
  • fuel inlet holes 14 are made in the wall of the body 1 of the pump, at a predetermined distance below the inlet ports 4.
  • the holes 14 and the ports 4 are connected to a relatively low pressure fuel source.
  • the distance, in the axial direction of the piston, between the inlet orifices 4 and the inlet holes 14, the distance between the upper surface 15 of the piston 2, on the one hand, and the edges of the two grooves 5 and 9 , on the other hand, as well as the axial height of the flange 13 and the width of the second groove 9 are chosen to ensure the specific operating steps of the pump shown in FIGS. 1 to 4.
  • the intake chamber 3 communicates with the inlet orifices 4, which allows the filling of the chamber 3 with fuel.
  • the piston 2 By moving upwards, that is to say towards its top dead center position, the piston 2 reaches the position illustrated in FIG. 2, in which it begins to close the inlet orifices 4. Since the flange 13 is located opposite the holes for inlet 14 and closes these, no more communication exists between the chamber 3 and a low pressure fuel inlet conduit. This is the start of fuel delivery to the injector in the direction of arrow F1. This beginning of repression is designated in Figure 6 by the letter A.
  • the position of the bottom dead center of the piston 2 relative to the movement of the piston of the engine cylinder is chosen such that the start A of the first phase of injection into the engine cylinder is sufficiently advanced relative to the top dead center of the piston of said engine cylinder so that this first injection can constitute a pre-injection ensuring ignition ? in the combustion chamber of an engine cylinder, the amount of main injection combustion, with practically no ignition delay.
  • the start of preinjection could take place at a time corresponding to an angle of rotation of approximately -30 ° from the crankshaft, before the top dead center of the engine piston and the main injection could be triggered at an angle of about -15 °.
  • these values are given only by way of example.
  • the effect of the pre-injection varies as a function of the speed of rotation of the engine.
  • the illustration of the first repression phase that is to say the pre-injection repression, in the form of a rectangle according to FIG. 6, corresponds to the phenomena which actually occur.
  • the delivery and the pre-injection take on the form of a shower, because the establishment of the relatively high pressure inside the chamber 3 during the delivery of fuel out of the chamber and the drop in pressure in the chamber due to the communication between the latter and the inlet holes 14 require a certain period of time, since the inlet orifices 4 and the inlet holes 14 have cross sections of limited value.
  • the upper and lower edges 10, 11 of the second groove 9 are straight and circular. However, it is possible to configure at least one edge, for example the upper edge, at least partially in a helical ramp. This would make it possible to vary the instant of the end of the pre-injection delivery (B in FIG. 6), by rotation of the piston 2 around its longitudinal axis. An appropriate configuration of the lower edge of the groove 9 would make it possible to modify the start of the main injection delivery (C).
  • FIGS. 2 to 5 comprises a circular groove 9 and twice two inlet holes 14, and this in order to reduce the height of the groove 9 and the diameters of said holes 14, because these two dimensions decide the distance between B and C in Figure 6, that is to say the time of the pre-injection compared to the main injection, on the one hand, and the lifting of the cam corresponding to this period, d 'somewhere else.
  • These measures make it possible to reduce the length of the inactive part, that is to say without the piston stroke being pushed back, advance the start of the main injection delivery and / or delay the start of the pre-injection delivery.
  • FIGS. 7 and 8 show another embodiment of the injection pump according to the invention, in which the inlet holes 14 ′ - two in number in the example shown - are located approximately at the same level as the orifices inlet 4.
  • Two grooves 9 ' which function corresponds to that of the circular groove 9 of the first embodiment are formed in the peripheral surface of the piston, at a predetermined distance from the upper surface 15 of the piston, substantially parallel to that -this.
  • each groove 9 ' opens at one end into a vertical groove 8 and thus communicates, permanently, with the interior of the intake chamber 3.
  • each groove could be in communication with this chamber by its two ends.
  • the operation of this embodiment is the same, in principle, as that illustrated in FIGS. 1 to 4.
  • the pre-injection delivery begins when the orifices 4 are closed by the piston.
  • the inlet holes 14 ' are closed by the part of the peripheral surface 13' of the piston which is located above the grooves 9 '. This discharge is finished at the moment when the grooves 9 'come opposite the holes 14'.
  • the main injection delivery begins after the holes 14 'are closed by the peripheral surface of the piston located below the grooves 9' and ends when the ramp 7 discovers the orifices 4.
  • the injection pump according to the present invention also comprises means which allow the variation of the start of the pre-injection delivery. These means are formed by an accumulator device.
  • the accumulator comprises an accumulator chamber 16 in which is mounted a piston 17 movable against a return spring 18.
  • the chamber 16 communicates permanently with the chamber inlet 3 of the injection pump through a passage 19 which opens into the chamber 3 at a level above the top dead center of the piston.
  • the rear part 20 of the chamber, which houses the spring 18, is in permanent communication with the space 21 from which the inlet orifices leave. This ensures that a relatively low pressure acts on the rear face of the piston 17.
  • the stroke of the piston 17 is limited by a stop 22 formed for example by a shoulder of the wall of the chamber 16.
  • the piston 17 is movable over a length e.
  • the stop 22 is shaped as a sealed seat to produce a sealing barrier between the chamber 16 and the part 20 of the chamber containing the spring 18, when the piston is pushed against the stop under the effect of the high pressure prevailing in chamber 3 of the pump and chamber 16,, during the delivery of fuel to the injector.
  • This accumulator operates as follows: When after closing the inlet orifices 4, the piston 2 continues its upward stroke, the pressure inside the receiving chamber 3 increases only slowly since the decrease in the volume of the receiving chamber 3 is compensated by an increase in the volume of the accumulating chamber 16 because the piston 17 moves back under the effect of the increase in the pressure. Consequently, the pressure which is necessary for the opening of the discharge valve 23 can only be established after the piston has come into contact on its sealed seat stop 22. This means that point A, in the figure 6, moves to point B and the amount of pre-injection fuel delivered decreases. On the other hand, the interruption of the discharge at point B is independent of the accumulator and determined only by the communication of the additional holes 14 and the throat 9 of interruption of the discharge. Although the pressure inside the chamber 3 falls, it remains however, due to the piston which continues its upward stroke, at a value sufficient for the maintenance on its seat of the piston 17 of the accumulator.
  • the accumulator has no influence on the start of the main injection delivery, but makes it possible to vary the start of the pre-injection delivery (point A in FIG. 6), and thus the quantity of the pre-injection fuel.
  • FIGS 7 and 8 illustrate two embodiments of the accumulator 15 according to the invention.
  • the accumulator is placed next to the device forming a discharge member 23, above the inlet chamber 3 of the injection pump.
  • the accumulator is perfectly incorporated into the structure of the pump.
  • the accumulator shown in Figure 11 is made to allow adjustment of the outside of the start of the pre-injection delivery.
  • a rod 24 is fixed to the rear face of the piston 17. The free end of said rod comes out of the pump. Rod 24 can be controlled from outside the pump, which makes it easy to vary the final position of the piston 17. It is also possible to deactivate the pre-injection.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fuel-Injection Apparatus (AREA)

Abstract

Pompe d'injection permettant de réaliser une préinjection et une injection principale pendant la course de refoulement du piston (2). Pour effectuer la préinjection, le refoulement du combustible hors de la chambre d'admission (3) vers l'injecteur est interrompu lorsque l'arête supérieure (10) de la gorge circulaire (9) du piston (2), qui est en communication permanente avec la chambre (3), vient au niveau du bord inférieur des trous d'arrivée de combustible (14). Après la fermeture des trous (14) par le bord inférieur (11) de la gorge (9), lors de la course ascendante du piston (2), le refoulement du combustible vers l'injecteur reprend et la phase de l'injection principale commence. Cette phase est terminée lorsque la rampe hélicoïdale (7) vient en regard de l'orifice d'arrivée du combustible (4).Injection pump for pre-injection and main injection during the piston delivery stroke (2). To carry out the pre-injection, the delivery of the fuel out of the intake chamber (3) to the injector is interrupted when the upper edge (10) of the circular groove (9) of the piston (2), which is in communication permanent with the chamber (3), comes at the lower edge of the fuel inlet holes (14). After the holes (14) are closed by the lower edge (11) of the groove (9), during the upward stroke of the piston (2), the delivery of fuel to the injector resumes and the phase of the main injection start. This phase is completed when the helical ramp (7) comes opposite the fuel inlet orifice (4).

Description

L'invention concerne une pompe d'injection pour l'injection de combustible dans un cylindre d'un moteur à combustion interne.The invention relates to an injection pump for injecting fuel into a cylinder of an internal combustion engine.

L'invention a particulièrement pour objet une pompe d'injection comprenant une chambre réceptrice de combustible délimitée dans un corps cylindrique, et variable en volume par le déplacement dans ce corps, d'un piston, suivant un mouvement alternatif de va-et-vient, entre une position de point mort haut et une position de point mort bas, cette chambre étant pourvue au moins d'un orifice d'arrivée d'un combustible, relié à une source de combustible de relativement faible pression et obturable lors du déplacement dudit piston à partir de sa position de point mort bas vers sa position de point mort haut, pour permettre le refoulement de combustible hors de ladite chambre vers un injecteur associé à un cylindre du moteur, et le piston comportant au moins une rampe hélicoïdale à sa périphérie, qui aboutit à une rainure axiale et une gorge circulaire reliée par ladite rainure axiale à l'intérieur de ladite chambre réceptrice.The invention particularly relates to an injection pump comprising a fuel receiving chamber defined in a cylindrical body, and variable in volume by the movement in this body, of a piston, according to an alternating back and forth movement , between a top dead center position and a bottom dead center position, this chamber being provided with at least one fuel inlet orifice, connected to a source of fuel of relatively low pressure and closable during the movement of said piston from its bottom dead center position to its top dead center position, to allow fuel to be discharged from said chamber to an injector associated with an engine cylinder, and the piston comprising at least one helical ramp at its periphery , which results in an axial groove and a circular groove connected by said axial groove inside said receiving chamber.

Les pompes d'injection connues de cette structure ont pour inconvénient que la quantité de combustible injectée dans un cylindre, avant l'allumage, peut devenir relativement grande en cas d'un long délai d'allumage provoqué par l'air trop froid ou un combustible de mauvaise qualité. Quand l'allumage se produit enfin, une grande quantité de combustible s'enflamme, ce qui a pour conséquence une forte augmentation de la pression à l'intérieur de la chambre de combustion provoquant des fortes contraintes dans les pièces constitutives du moteur, comme la chemise, dans les paliers de l'arbre, des problèmes d'étanchéité, par exemple au niveau du joint de culasse, et du bruit.The known injection pumps of this structure have the disadvantage that the quantity of fuel injected into a cylinder, before ignition, can become relatively large in the event of a long ignition delay caused by too cold air or poor quality fuel. When ignition finally occurs, a large amount of fuel ignites, which results in a sharp increase in pressure inside the combustion chamber causing great stresses in the component parts of the engine, such as the jacket, in the shaft bearings, sealing problems, for example at the head gasket, and noise.

On sait qu'il est possible d'éliminer ces inconvénients en effectuant, avant l'injection principale, une préinjection. En allumant tout d'abord la faible quantité de combustible de préinjection on assure l'allumage du combustible d'injection principale qui se fait pratiquement sans délai d'allumage. Mais, la préinjection, telle qu'elle est effectuée jusqu'à présent, nécessite des moyens supplémentaires complexes et difficiles à mettre en oeuvre.We know that it is possible to eliminate these drawbacks by performing a pre-injection before the main injection. By first lighting the small amount of pre-injection fuel, the main injection fuel is ignited, which takes place almost without ignition delay. However, pre-injection, as it has been done up to now, requires additional means which are complex and difficult to implement.

L'invention a pour objectif de proposer une pompe d'injection qui permet de réaliser la préinjection grâce à une configuration appropriée, de la pompe d'injection du type décrit plus haut.The object of the invention is to propose an injection pump which makes it possible to carry out the pre-injection by means of an appropriate configuration, of the injection pump of the type described above.

Pour atteindre ce but, le piston de la pompe d'injection comprend un passage s'ouvrant à une extrémité dans ladite chambre réceptrice de combustible et susceptible de venir en communication, par son autre extrémité, avec au moins un canal débouchant dans l'espace intérieur du corps provenant de ladite source de combustible, pour interrompre à un instant prédéterminé et pendant une durée prédéterminée le refoulement de combustible hors de ladite chambre vers L'injecteur au cours du déplacement du piston en direction de son point mort haut, la première phase de refoulement permettant unepré-injectionde combustible dans ledit cylindre et la deuxième phase de refoulement assurant une injection principale.To achieve this goal, the piston of the injection pump comprises a passage opening at one end into said fuel receiving chamber and capable of coming into communication, through its other end, with at least one channel opening into space inside the body coming from said fuel source, to interrupt at a predetermined time and for a predetermined period the delivery of fuel from said chamber to The injector during the displacement of the piston in the direction of its top dead center, the first delivery phase allowing a pre-injection of fuel into said cylinder and the second delivery phase ensuring a main injection.

Selon une caractéristique avantageuse de l'invention, le piston comprend en dessous de ladite première gorge une deuxième gorge périphérique communiquant avec la première gorge, et le corps de la pompe d'injection comporte au moins un canal d'arrivée précité, situé en dessous des orifices d'arrivée et obturable par la surface périphérique du piston, le canal d'arrivée et ladite deuxième gorge étant disposés de façon que la gorge est susceptible de venir en regard dudit canal à un instant prédéterminé après l'obturation des orifices d'arrivée par ledit piston, pendant le déplacement de refoulement de celui-ci en direction de son point mort haut.According to an advantageous characteristic of the invention, the piston comprises below said first groove a second peripheral groove communicating with the first groove, and the body of the injection pump comprises at least one aforementioned inlet channel, located below inlet orifices and closable by the peripheral surface of the piston, the inlet channel and said second groove being arranged so that the groove is capable of coming opposite said channel at a predetermined instant after the obturation of the orifices arrival by said piston, during the displacement displacement of the latter in the direction of its top dead center.

La pompe d'injection selon l'invention comprend en outre un dispositif accumulateur de combustible permettant une variation de la quantité de combustible de préinjection sans influencer le début de l'injection principale.The injection pump according to the invention further comprises a fuel accumulator device allowing a variation in the quantity of pre-injection fuel without influencing the start of the main injection.

L'invention sera mieux comprise, et d'autres buts, caractéristiques, détails et avantages de celle-ci apparaîtront plus clairement au cours de la description explicative qui va suivre faite en référence aux dessins schématiques annexés donnés uniquement à titre d'exemple illustrant deux modes de réalisation de l'invention et dans lesquels :The invention will be better understood, and other objects, characteristics, details and advantages thereof will appear more clearly during the explanatory description which follows, made with reference to the appended schematic drawings given solely by way of example illustrating two embodiments of the invention and in which:

Les figures 1 à 4 sont des vues en coupe longitudinales d'un premier mode de réalisation d'une pompe d'injection selon l'invention et illustrent des étapes spécifiques du fonctionnement de la pompe; la figure 5 est une vue en coupe suivant la ligne V-V de la figure 2; la figure 6 illustre les phases de refoulement de combustible hors de la chambre de la pompe d'injection, en fonction de la position du piston du cylindre du moteur, exprimé en position angulaire de l'arbre manivelle; la figure 7 est une vue en coupe longitudinale d'un deuxième mode de réalisation d'une pompe d'injection selon l'invention; la figure 8 est une vue en coupe suivant la ligne VIII-VIII de la figure 7; la figure 9 montre en une vue en coupe et de façon schématique le dispositif accumulateur selon l'invention, et les figures 10 et 11 illustrent deux modes de réalisation concrètesd'un accumulateur selon l'invention.Figures 1 to 4 are longitudinal sectional views of a first embodiment of an injection pump according to the invention and illustrate specific steps in the operation of the pump; Figure 5 is a sectional view along line V-V of Figure 2; FIG. 6 illustrates the fuel delivery phases out of the injection pump chamber, as a function of the position of the piston of the engine cylinder, expressed in angular position of the crankshaft; Figure 7 is a longitudinal sectional view of a second embodiment of an injection pump according to the invention; Figure 8 is a sectional view along line VIII-VIII of Figure 7; Figure 9 shows in a sectional view and schematically the accumulator device according to the invention, and Figures 10 and 11 illustrate two concrete embodiments of an accumulator according to the invention.

La pompe d'injection représentée sur les figures 1 à 5 comprend un corps cylindrique 1 et un piston 2 monté mobile dans ce corps 1 suivant un mouvement alternatif rectiligne de va-et-vient, entre une position de point mort bas et une position de point mort haut, sous l'effet d'une came de commande (non représentée) solidaire d'un arbre mû par le moteur.The injection pump shown in Figures 1 to 5 comprises a cylindrical body 1 and a piston 2 movably mounted in this body 1 in a reciprocating rectilinear reciprocating movement, between a position of bottom dead center and a position of top dead center, under the effect of a control cam (not shown) secured to a shaft driven by the motor.

Dans le corps 1, au-dessus du piston 2, est délimitée une chambre d'admission de combustible 3, dans laquelle débouchent des orifices d'arrivée de combustible 4. Ces orifices sont situés à un niveau tel qu'ils permettent le remplissage de la chambre 3 par le combustible, lorsque le piston occupe sa position de point mort bas. En haut de la chambre, non représenté, il faut imaginer un orifice de refoulement de combustible en direction de la flèche F1, vers un injecteur associé à un cylindre d'un moteur à combustion interne. Cet orifice de refoulement est obturable par un organe de décharge, de façon connue en soi.In the body 1, above the piston 2, is defined a fuel intake chamber 3, into which open fuel inlet orifices 4. These orifices are located at a level such that they allow the filling of the chamber 3 by the fuel, when the piston occupies its bottom dead center position. At the top of the chamber, not shown, it is necessary to imagine a fuel delivery orifice in the direction of arrow F1, towards an injector associated with a cylinder of an internal combustion engine. This discharge orifice can be closed off by a discharge member, in a manner known per se.

Le piston 2 comporte une première gorge circulaire 5 délimitée à sa partie inférieure par une arête droite 6 et à sa partie supérieure par une arête hélicoïdale 7 formant une rampe hélicoïdale et aboutissant à une rainure 8 qui s'étend parallèlement à l'axe du piston. Cette rainure établit une communication permanente entre la chambre d'admission 3 et la gorge 5. Jusqu'ici la structure du piston et du corps est connue.The piston 2 has a first circular groove 5 delimited at its lower part by a straight edge 6 and at its upper part by a helical edge 7 forming a helical ramp and ending in a groove 8 which extends parallel to the axis of the piston . This groove establishes permanent communication between the inlet chamber 3 and the groove 5. Up to now, the structure of the piston and of the body is known.

Selon l'invention, le piston 2 est pourvu d'une deuxième gorge circulaire 9, limitée, dans l'exemple représenté, en haut par une arête droite 10 et en bas par une arête droite 11. Cette deuxième gorge 9 communique avec la première gorge 5 à travers des passages axiaux, formés dans l'exemple représenté par deux méplats 12 pratiqués sur la collerette 13 qui est délimitée entre les deux gorges 5 et 9. Il est à noter que les arêtes 6, 7, 10 et 11 présentent chacune un angle vif de 90°.According to the invention, the piston 2 is provided with a second circular groove 9, limited, in the example shown, above by a straight edge 10 and below by a straight edge 11. This second groove 9 communicates with the first groove 5 through axial passages, formed in the example represented by two flats 12 formed on the flange 13 which is delimited between the two grooves 5 and 9. It should be noted that the edges 6, 7, 10 and 11 each have a sharp angle of 90 °.

Comme il ressort des figures, des trous d'arrivée 14 du combustible sont pratiqués dans la paroi du corps 1 de la pompe, à une distance prédéterminée en dessous des orifices d'arrivée 4. Les trous 14 et les orifices 4 sont reliés à une source de combustible de relativement faible pression.As shown in the figures, fuel inlet holes 14 are made in the wall of the body 1 of the pump, at a predetermined distance below the inlet ports 4. The holes 14 and the ports 4 are connected to a relatively low pressure fuel source.

La distance,dans le sens axial du piston, entre les orifices d'arrivée 4 et les trous d'arrivée 14, la distance entre la surface supérieure 15 du piston 2, d'une part, et les arêtes des deux gorges 5 et 9, d'autre part, ainsi que la hauteur axiale de la collerette 13 et la largeur de la deuxième gorge 9 sont choisies pour assurer les étapes de fonctionnement spécifiques de la pompe représentées sur les figures 1 à 4.The distance, in the axial direction of the piston, between the inlet orifices 4 and the inlet holes 14, the distance between the upper surface 15 of the piston 2, on the one hand, and the edges of the two grooves 5 and 9 , on the other hand, as well as the axial height of the flange 13 and the width of the second groove 9 are chosen to ensure the specific operating steps of the pump shown in FIGS. 1 to 4.

Dans la position du piston, représentée sur la figure 1, la chambre d'admission 3 communique avec les orifices d'arrivée 4, ce qui permet le remplissage en combustible de la chambre 3. En se déplaçant vers le haut, c'est-à-dire vers sa position de point mort haut, le piston 2 atteint la position illustrée sur la figure 2, dans laquelle il commence à obturer les orifices d'arrivée 4. Etant donné que la collerette 13 se trouve en face des trous d'arrivée 14 et obture ceux-ci, plus aucune communication n'existe entre la chambre 3 et un conduit d'arrivée de combustible de faible pression. C'est le début de refoulement de combustible vers l'injecteur dans la direction de la flèche F1. Ce début de refoulement est désigné sur la figure 6 par la lettre A.In the position of the piston, shown in FIG. 1, the intake chamber 3 communicates with the inlet orifices 4, which allows the filling of the chamber 3 with fuel. By moving upwards, that is to say towards its top dead center position, the piston 2 reaches the position illustrated in FIG. 2, in which it begins to close the inlet orifices 4. Since the flange 13 is located opposite the holes for inlet 14 and closes these, no more communication exists between the chamber 3 and a low pressure fuel inlet conduit. This is the start of fuel delivery to the injector in the direction of arrow F1. This beginning of repression is designated in Figure 6 by the letter A.

En continuant sa course de montée, le piston 2 arrive à la position montrée sur la figure 3, dans laquelle l'arête supérieure 10 de la deuxième gorge 9 circulaire vient au niveau du bord inférieur des trous d'arrivée 14, ce qui constitue le début de la mise en communication de ces trous 14 et de la gorge 9 et, à travers les méplats 12, de la gorge 5 et de la rainure 8, avec la chambre 3. Il en résulte une brusque chute de pression à l'intérieur de la chambre 3. Le refoulement de combustible s'arrête, bien que le piston continue sa course de montée. Cet état est indiqué sur la figure 6 par la lettre B. Cette communication et en raison d'elle la faible pression à l'intérieur de la chambre 3 persistent jusqu'à ce que le piston atteigne la position représentée sur la figure 4, dans laquelle l'arête inférieure 11 de la gorge 9 vient au niveau du bord supérieur des trous d'arrivée 14. Ceux-ci se trouvent obturés par la surface cylindrique du piston, qui fait suite à la gorge 9. Dans cette position les orifices d'arrivée 4 sont encore fermés. La chambre 3 ainsi coupée des conduits de faible pression 4, 14, la pression du combustible à l'inté- ieur de la chambre augmente et le refoulement de combustible vers l'injecteur reprend, comme ceci est indiqué par la lettre C sur la figure 6. Le refoulement prend fin en D, lorsque la rampe hélicoïdale 7 vient en regard d'un orifice d'arrivée 4. L'injection est plus rapide entre C et D qu'entre A et B, car la vitesse de la came de commande du piston est encore faible entre A et B, étant donné qu'elle se situe relativement au début de la montée du piston.Continuing its upward stroke, the piston 2 arrives at the position shown in FIG. 3, in which the upper edge 10 of the second circular groove 9 comes at the level of the lower edge of the inlet holes 14, which constitutes the start of the communication of these holes 14 and the groove 9 and, through the flats 12, of the groove 5 and the groove 8, with the chamber 3. This results in a sudden drop in pressure inside from room 3. The repression of fuel stops, although the piston continues its upward stroke. This state is indicated in Figure 6 by the letter B. This communication and because of it the low pressure inside the chamber 3 persist until the piston reaches the position shown in Figure 4, in which the lower edge 11 of the groove 9 comes to the level of the upper edge of the inlet holes 14. These are closed by the cylindrical surface of the piston, which follows the groove 9. In this position the orifices d 'arrival 4 are still closed. The chamber 3 thus cut off from the low pressure conduits 4, 14, the fuel pressure inside the chamber increases and the fuel delivery towards the injector resumes, as indicated by the letter C in the figure 6. The discharge ends in D, when the helical ramp 7 comes opposite an inlet orifice 4. The injection is faster between C and D than between A and B, because the speed of the cam piston control is still weak between A and B, since it is located relatively to the start of the piston rise.

La position du point mort bas du piston 2 par rapport au mouvement du piston du cylindre du moteur est choisie telle que le début A de la première phase d'injection dans le cylindre du moteur est suffisamment avancé par rapport au point mort haut du piston dudit cylindre du moteur pour que cette première injection puisse constituer une préinjection assurant l'allumage'? dans la chambre de combustion d'un cylindre du moteur, de la quantité de combustion d'injection prin- pale, pratiquement sans délai d'allumage. Par exemple le début de préinjection pourrait avoir lieu à un instant correspondant à un angle de rotation d'environ -30° de l'arbre manivelle, avant le point mort haut du piston moteur et l'injection principale pourrait être déclenchée à un angle d'environ -15°. Bien entendu, ces valeurs sont données uniquement à titre d'exemple.The position of the bottom dead center of the piston 2 relative to the movement of the piston of the engine cylinder is chosen such that the start A of the first phase of injection into the engine cylinder is sufficiently advanced relative to the top dead center of the piston of said engine cylinder so that this first injection can constitute a pre-injection ensuring ignition ? in the combustion chamber of an engine cylinder, the amount of main injection combustion, with practically no ignition delay. For example, the start of preinjection could take place at a time corresponding to an angle of rotation of approximately -30 ° from the crankshaft, before the top dead center of the engine piston and the main injection could be triggered at an angle of about -15 °. Of course, these values are given only by way of example.

Il s'est avéré que l'effet de la préinjection varie en fonction de la vitesse de rotation du moteur. A des vitesses relativement basses, l'illustration de la première phase de refoulement, c'est-à-dire du refoulement de préinjection, sous forme d'un rectangle suivant la figure 6, correspond aux phénomènes qui se produisent réellement.It has been found that the effect of the pre-injection varies as a function of the speed of rotation of the engine. At relatively low speeds, the illustration of the first repression phase, that is to say the pre-injection repression, in the form of a rectangle according to FIG. 6, corresponds to the phenomena which actually occur.

Mais, à des vitesses plus élevées, le refoulement et la préinjection, en fonction du temps, prennent plutôt l'allure d'une doche, du fait que l'établissement de la pression relativement élevée à l'intérieur de la chambre 3 pendant le refoulement de combustible hors de la chambre et la chute de la pression dans la chambre en raison de la mise en communication de celle-ci avec les trous d'arrivée 14 nécessitent un certain délai de temps, puisque les orifices d'arrivée 4 et les trous d'arrivée 14 présentent des sections transversales de valeur limitée.However, at higher speeds, the delivery and the pre-injection, as a function of time, take on the form of a shower, because the establishment of the relatively high pressure inside the chamber 3 during the delivery of fuel out of the chamber and the drop in pressure in the chamber due to the communication between the latter and the inlet holes 14 require a certain period of time, since the inlet orifices 4 and the inlet holes 14 have cross sections of limited value.

Ainsi, à des vitesses de rotation élevées, la pression augmentera dans la chambre avant l'obturation des orifices d'arrivée 4 et le découvrement des trous d'arrivée 14 par la collerette 13 n'entraînera pas tout de suite la chute de la pression dans la chambre. Par conséquent, un refoulement de combustible et un effet d'injection se produiront même à vitesse élevée du moteur, lorsque l'ouverture des trous 14 intervient avant l'obturation des orifices. Ce refoulement de combustible hors de la chambre par effet de "laminage" peut se produire par exemple pour un piston pourvu d'un cran dans sa surface supérieure 15 et fonctionnant à une position angulaire dans laquelle le cran vient en regard des orifices d'arrivée 4, ce qui retarde la fermeture de ces orifices. Si le cran est suffisamment profond, la gorge 9 peut venir en face des trous 14 avant l'obturation des orifices d'arrivée. A faible vitesse, la phase de refoulement A-B (figure 6) ne se produirait pas. Mais, à pleine vitesse, grâce à l'effet de laminage, il y aura quand même un refoulement et une préinjection.Thus, at high rotational speeds, the pressure will increase in the chamber before closing the inlet orifices 4 and the uncovering of the inlet holes 14 by the flange 13 will not immediately cause the pressure to drop in the bedroom. Consequently, a fuel backflow and an injection effect will occur even at high engine speed, when the opening of the holes 14 occurs before the orifices are closed. This delivery of fuel out of the chamber by "rolling" effect may occur for example for a piston provided with a notch in its upper surface 15 and operating at an angular position in which the notch comes opposite the inlet orifices 4, which delays the closing of these orifices. If the notch is deep enough, the groove 9 can come in front of the holes 14 before closing the inlet orifices. At low speed, the backflow phase AB (Figure 6) would not occur. However, at full speed, thanks to the rolling effect, there will still be a backflow and a pre-injection.

Dans l'exemple décrit et représenté, les arêtes supérieure et inférieure 10, 11 de la deuxième gorge 9 sont droites et circulaires. Mais, il est possible de configurer au moins une arête, par exemple l'arête supérieure, au moins partiellement en rampe hélicoïdale. Ceci permettrait de varier l'instant de la fin du refoulement de préinjection (B sur la figure 6), par rotation du piston 2 autour de son axe longitudinal. Une configuration appropriée de l'arête inférieure de la gorge 9 permettrait de modifier le début du refoulement d'injection principale (C).In the example described and shown, the upper and lower edges 10, 11 of the second groove 9 are straight and circular. However, it is possible to configure at least one edge, for example the upper edge, at least partially in a helical ramp. This would make it possible to vary the instant of the end of the pre-injection delivery (B in FIG. 6), by rotation of the piston 2 around its longitudinal axis. An appropriate configuration of the lower edge of the groove 9 would make it possible to modify the start of the main injection delivery (C).

Le mode de réalisation représenté par les figures 2 à 5 comprend une gorge 9 circulaire et deux fois deux trous d'arrivée 14, et ceci dans le but de réduire la hauteur de la gorge 9 et les diamètres desdits trous 14, car ces deux dimensions décident de la distance entre B et C sur la figure 6, c'est-à-dire le moment de la préinjection par rapport à l'injection principale, d'une part, et la levée de la came correspondant à cette période, d'autre part. Ces mesures permettent de diminuer la longueur de la partie inactive, c'est-à-dire sans refoulement de la course du piston, d'avancer le début du refoulement d'injection principale et/ou retarder le début du refoulement de préinjection.The embodiment represented by FIGS. 2 to 5 comprises a circular groove 9 and twice two inlet holes 14, and this in order to reduce the height of the groove 9 and the diameters of said holes 14, because these two dimensions decide the distance between B and C in Figure 6, that is to say the time of the pre-injection compared to the main injection, on the one hand, and the lifting of the cam corresponding to this period, d 'somewhere else. These measures make it possible to reduce the length of the inactive part, that is to say without the piston stroke being pushed back, advance the start of the main injection delivery and / or delay the start of the pre-injection delivery.

Les figures 7 et 8 montrent un autr4node de réalisation de la pompe d'injection selon l'invention, dans lequel les trous d'arrivée 14' -au nombre de deux dans l'exemple représenté- sont situés approximativement au même niveau que les orifices d'arrivée 4. Deux gorges 9' dont la fonction correspond à celle de la gorge circulaire 9 du premier mode de réalisation sont pratiquées dans la surface périphérique du piston, à une distance prédéterminée de la surface supérieure 15 du piston, sensiblement parallèlement à celle-ci.FIGS. 7 and 8 show another embodiment of the injection pump according to the invention, in which the inlet holes 14 ′ - two in number in the example shown - are located approximately at the same level as the orifices inlet 4. Two grooves 9 'whose function corresponds to that of the circular groove 9 of the first embodiment are formed in the peripheral surface of the piston, at a predetermined distance from the upper surface 15 of the piston, substantially parallel to that -this.

Comme il ressort clairement des figures 7 et 8, chaque gorge 9' débouche à une extrémité dans une rainure verticale 8 et communique ainsi, de façon permanente, avec l'intérieur de la chambre d'admission 3. Selon une variante de réalisation, chaque rainure pourrait être en communication avec cette chambre par ses deux extrémités.As is clear from Figures 7 and 8, each groove 9 'opens at one end into a vertical groove 8 and thus communicates, permanently, with the interior of the intake chamber 3. According to an alternative embodiment, each groove could be in communication with this chamber by its two ends.

Le fonctionnement de ce mode de réalisation est le même, au niveau du principe, que celui illustré par les figures 1 à 4. Le refoulement de préinjection débute lorsque les orifices 4 sont obturés par le piston. Les trous d'arrivée 14' sont fermés par la partie de la surface périphérique 13' du piston qui se trouve au-dessus des gorges 9'. Ce refoulement est terminé à l'instant où les gorges 9' viennent en regard des trous 14'. Le refoulement d'injection principale commence après l'obturation des trous 14' par la surface périphérique du piston situé en dessous des gorges 9' et prend fin lorsque la rampe 7 découvre les orifices 4. La pompe d'injection selon la présente invention comprend également des moyens qui permettent la variation du début du refoulement de préinjection. Ces moyens sont formés par un dispositif accumulateur. Selon la représentation schématique donnée par la figure 9, l'accumulateur comprend une chambre accumulatrice 16 dans laquelle est monté un piston 17 mobile à l'encontre d'un ressort de rappel 18. La chambre 16 communique de façon permanente avec la chambre d'admission 3 de la pompe d'injection par un passage 19 qui débouche dans la chambre 3 à un niveau au-dessus du point mort haut du piston. La partie arrière 20 de la chambre, qui loge le ressort 18,est en communication permanente avec l'espace 21 d'où partent les orifices d'arrivée. Ceci assure qu'une pression relativement basse agit sur la face arrière du piston 17. La course du piston 17 est limitée par une butée 22 formée par exemple par un épaulement de la paroi de la chambre 16. Le piston 17 est déplaçable sur une longueur e. La butée 22 est conformée en siège étanche pour produire une barrière d'étanchéité entre la chambre 16 et la partie 20 de la chambre contenant le ressort 18, lorsque le piston est poussé contre la butée sous l'effet de la forte pression qui règne dans la chambre 3 de la pompe et la chambre 16,,lors du refoulement du combustible vers l'injecteur.The operation of this embodiment is the same, in principle, as that illustrated in FIGS. 1 to 4. The pre-injection delivery begins when the orifices 4 are closed by the piston. The inlet holes 14 'are closed by the part of the peripheral surface 13' of the piston which is located above the grooves 9 '. This discharge is finished at the moment when the grooves 9 'come opposite the holes 14'. The main injection delivery begins after the holes 14 'are closed by the peripheral surface of the piston located below the grooves 9' and ends when the ramp 7 discovers the orifices 4. The injection pump according to the present invention also comprises means which allow the variation of the start of the pre-injection delivery. These means are formed by an accumulator device. According to the schematic representation given in Figure 9, the accumulator comprises an accumulator chamber 16 in which is mounted a piston 17 movable against a return spring 18. The chamber 16 communicates permanently with the chamber inlet 3 of the injection pump through a passage 19 which opens into the chamber 3 at a level above the top dead center of the piston. The rear part 20 of the chamber, which houses the spring 18, is in permanent communication with the space 21 from which the inlet orifices leave. This ensures that a relatively low pressure acts on the rear face of the piston 17. The stroke of the piston 17 is limited by a stop 22 formed for example by a shoulder of the wall of the chamber 16. The piston 17 is movable over a length e. The stop 22 is shaped as a sealed seat to produce a sealing barrier between the chamber 16 and the part 20 of the chamber containing the spring 18, when the piston is pushed against the stop under the effect of the high pressure prevailing in chamber 3 of the pump and chamber 16,, during the delivery of fuel to the injector.

Cet accumulateur fonctionne de la façon suivante : Lorsqu'après obturation des orifices d'arrivée 4,le piston 2 continue sa course de montée, la pression à l'intérieur de la chambre 3 réceptrice n'augmente que doucement puisque la diminution du volume de la chambre réceptrice 3 est compensée par une augmentation du volume de la chambre accumulatrice 16 du fait que le piston 17 recule sous l'effet de l'augmentation de la pression. Par conséquent, la pression qui est nécessaire pour l'ouverture du clapet de refoulement 23 ne peut s'établir qu'après que le piston soit venu en contact sur sa butée de siège étanche 22. Ceci signifie que le point A, sur la figure 6, se déplace vers le point B et que la quantité de combustible de préinjection refoulé diminue. Par contre, l'interruption du refoulement au point B est indépendant de l'accumulateur et déterminéuniquement par la mise en communication des trous supplémentaires 14 et de la gorge 9 d'interruption du refoulement.Bien.que la pression à l'intérieur de la chambre 3 tombe, elle reste cependant, en raison du piston qui continue sa course de montée, à une valeur suffisante pour le maintien sur son siège du piston 17 de l'accumulateur.This accumulator operates as follows: When after closing the inlet orifices 4, the piston 2 continues its upward stroke, the pressure inside the receiving chamber 3 increases only slowly since the decrease in the volume of the receiving chamber 3 is compensated by an increase in the volume of the accumulating chamber 16 because the piston 17 moves back under the effect of the increase in the pressure. Consequently, the pressure which is necessary for the opening of the discharge valve 23 can only be established after the piston has come into contact on its sealed seat stop 22. This means that point A, in the figure 6, moves to point B and the amount of pre-injection fuel delivered decreases. On the other hand, the interruption of the discharge at point B is independent of the accumulator and determined only by the communication of the additional holes 14 and the throat 9 of interruption of the discharge. Although the pressure inside the chamber 3 falls, it remains however, due to the piston which continues its upward stroke, at a value sufficient for the maintenance on its seat of the piston 17 of the accumulator.

Ceci signifie que l'accumulateur n'a aucune influence sur le début du refoulement d'injection principale, mais permet de faire varier le début du refoulement de préinjection (point A sur la figur6 6), et ainsi la quantité du combustible de préinjection.This means that the accumulator has no influence on the start of the main injection delivery, but makes it possible to vary the start of the pre-injection delivery (point A in FIG. 6), and thus the quantity of the pre-injection fuel.

Les figures 7 et 8 illustrent deux modes de réalisation de l'accumulateur 15 conforme à l'invention. Dans les deux cas, l'accumulateur est disposé à côté du dispositif formant organe de décharge 23, au-dessus de la chambre d'admission 3 de la pompe d'injection. Ainsi, l'accumulateur est parfaitement incorporé à la structure de la pompe.Figures 7 and 8 illustrate two embodiments of the accumulator 15 according to the invention. In both cases, the accumulator is placed next to the device forming a discharge member 23, above the inlet chamber 3 of the injection pump. Thus, the accumulator is perfectly incorporated into the structure of the pump.

L'accumulateur représenté sur la figure 11 est réalisé pour permettre un réglage de l'extérieur du début du refoulement de préinjection. A cet effet, une tige 24 est fixée à la face arrière du piston 17. L'extrémité libre de ladite tige ressort de la pompe. La tige 24 peut être commandée depuis l'extérieur de la pompe, ce qui permet de varier facilement la position finale du piston 17. Il est aussi possible de mettre hors service la préinjection.The accumulator shown in Figure 11 is made to allow adjustment of the outside of the start of the pre-injection delivery. To this end, a rod 24 is fixed to the rear face of the piston 17. The free end of said rod comes out of the pump. Rod 24 can be controlled from outside the pump, which makes it easy to vary the final position of the piston 17. It is also possible to deactivate the pre-injection.

Bien entendu, l'invention n'est nullement limitée aux modes de réalisation décrits et représentés qui n'ont été donnés qu'à titre d'exemple. En particulier, elle comprend tous les moyens constituant des équivalents techniques des moyens décrits, ainsi que leurs combinaisons, si celles-ci sont exécutées suivant son esprit et mises en oeuvre dans le cadre des revendications qui suivent.Of course, the invention is in no way limited to the embodiments described and shown which have been given only by way of example. In particular, it includes all the means constituting technical equivalents of the means described, as well as their combinations, if these are carried out according to the spirit and implemented in the context of the claims which follow.

Claims (14)

1.- Pompe d'injection pour l'injection de combustible dans un cylindre d'un moteur à combustion interne, du type comprenant une chambre réceptrice de combustible, délimitée dans un corps cylindrique et variable en volume par le déplacement dans ce corps d'un piston, suivant un mouvement rectiligne alternatif de va-et-vient, entre une position de point mort bas et une position de point mort haut, cette chambre étant pourvue d'orifices d'arrivée de combustible, reliés à une source de combustible de relativement faible pression et obturables par ledit piston, au cours de son déplacement. en direction de son point mort haut, pour permettre le refoulement de combustible hors de ladite chambre vers l'injecteur associé audit cylindre du moteur, ledit piston étant du type comportant une tête pourvue d'au moins une rampe hélicoïdale à sa périphérie, caractérisée en ce que le piston (2) comprend un passage s'ouvrant à une extrémité dans ladite chambre (3) et susceptible de venir en communication, par son autre extrémité, avec au moins un canal (14) relié à ladite source et débouchant dans l'espace interne dudit corps (1), dans lequel se déplace ledit piston (2), pour interrompre, à un instant prédéterminé et pendant une durée de temps prédéterminé, le refoulement de combustible hors de ladite chambre (3) vers l'injecteur, au cours du déplacement du piston (2) en direction dans son point mort haut, la première phase de refoulement permettant une préinjection de combustible dans ledit cylindre du moteur et la deuxième phase assurant une injection principale.1.- Injection pump for injecting fuel into a cylinder of an internal combustion engine, of the type comprising a fuel receiving chamber, delimited in a cylindrical body and variable in volume by the displacement in this body of a piston, in a reciprocating rectilinear reciprocating movement, between a bottom dead center position and a top dead center position, this chamber being provided with fuel inlet orifices, connected to a fuel fuel source relatively low pressure and closable by said piston, during its movement. towards its top dead center, to allow fuel to be discharged from said chamber to the injector associated with said engine cylinder, said piston being of the type comprising a head provided with at least one helical ramp at its periphery, characterized in that the piston (2) comprises a passage opening at one end into said chamber (3) and capable of coming into communication, through its other end, with at least one channel (14) connected to said source and opening into the the internal space of said body (1), in which said piston (2) moves, to interrupt, at a predetermined instant and for a predetermined period of time, the delivery of fuel from said chamber (3) to the injector, during the displacement of the piston (2) in direction in its top dead center, the first delivery phase allowing a pre-injection of fuel into said engine cylinder and the second phase ensuring a main injection. 2.- Pompe d'injection selon la revendication 1, caractérisée en ce que le piston (2) comprend, à une distance axiale prédéterminée en dessous de ladite tête à rampe hélicoïdale, une gorge périphérique circulaire (9) communiquant avec le passage précité, et que le corps (1) précité comporte au moins un canal d'arrivée (14) situé à une distance axiale prédéterminée en dessous des orifices d'arrivée (4) précités et obturable par la surface périphérique du piston (2), le canal d'arrivée (14) de combustible et ladite gorge (9) étant disposée de telle façon que la gorge (9) est susceptible de venir en regard du canal d'arrivée (14) du combustible à un instant prédéterminé après l'obturation desdits orifices d'arrivée par le piston, pendant son déplacement de refoulement en direction de son point mort haut.2.- injection pump according to claim 1, characterized in that the piston (2) comprises, at a predetermined axial distance below said helical ramp head, a circular peripheral groove (9) communicating with the aforementioned passage, and that the aforementioned body (1) comprises at least one inlet channel (14) located at a predetermined axial distance below the aforementioned inlet orifices (4) and closable by the peripheral surface of the piston (2), the fuel inlet channel (14) and said groove (9) being arranged such that the groove (9) is likely to come opposite the fuel inlet channel (14) at a predetermined instant after the said inlet orifices are closed off by the piston, during its displacement displacement towards its top dead center. 3.- Pompe d'injection selon la revendication 2, et comprenant un piston pourvu d'au moins une rampe hélicoïdale aboutissant à une extrémité dans une rainure axiale et à son autre extrémité à une gorge circulaire reliée par ladite rainure axiale à l'espace au-dessus dudit piston, formant ladite chambre, et caractérisée en ce que la gorge (9) permettant l'interruption du refoulement du combustible vers l'injecteur est séparée de ladite gorge (5) pratiquée dans la tête du piston par une collerette (13) pourvue de méplats (12) formant des passages entre lesdites gorges.3.- injection pump according to claim 2, and comprising a piston provided with at least one helical ramp leading to one end in an axial groove and at its other end to a circular groove connected by said axial groove to the space above said piston, forming said chamber, and characterized in that the groove (9) allowing the interruption of the delivery of fuel to the injector is separated from said groove (5) formed in the head of the piston by a flange ( 13) provided with flats (12) forming passages between said grooves. 4.- Pompe d'injection selon la revendication 3 comprenant deux rampes hélicoïdales aboutissant chacune à une extrémité dans une rainure axiale s'ouvrant dans la chambre d'admission, caractérisée en ce que, pour pouvoir réduire les diamètres des canaux d'arrivée et la hauteur de la gorge (9), deux paires de deux canaux (14) sont prévus.4.- injection pump according to claim 3 comprising two helical ramps each terminating at one end in an axial groove opening in the intake chamber, characterized in that, to be able to reduce the diameters of the inlet channels and the height of the groove (9), two pairs of two channels (14) are provided. 5.- Pompe d'injection selon la revendication 1, caractérisée en ce qu'au moins un canal (14') relié à la source de combustible de relativement faible pression est situé au moins approximativement au même niveau que les orifices d'arrivée (4) précités et qu'une gorge (9') pratiquée dans la surface périphérique du piston (2) à une distance prédéterminée de la surface supérieure (15) de refoulement du piston est associée à chaque canal,et cette gorge 9' formant partie du passage précité et étant en communication permanente avec l'intérieur de la chambre d'admission (3), est disposée de façon à pouvoir passer devant ledit canal (14') lors du déplacement du piston.5.- Injection pump according to claim 1, characterized in that at least one channel (14 ') connected to the fuel source of relatively low pressure is located at least approximately at the same level as the inlet orifices ( 4) above and that a groove (9 ') formed in the peripheral surface of the piston (2) at a predetermined distance from the upper surface (15) of the piston delivery is associated with each channel, and this groove 9' forming part of the aforementioned passage and being in permanent communication with the interior of the intake chamber (3), is arranged so as to be able to pass in front of said channel (14 ') when the piston moves. 6.- Pompe d'injection selon la revendication 5, comprenant un piston pourvu de deux rampes hélicoïdales aboutissant chacune à une extrémité dans une rainure axiale s'ouvrant dans la chambre d'admission de combustible, caractérisée en ce que deux canaux (14') précités sont prévus et que la gorge (9') précitée associée à chaque canal s'étend parallèlement à l'arête de la surface supérieure (15) du piston et débouche dans une desdites rainures verticales (8).6.- injection pump according to claim 5, comprising a piston provided with two helical ramps each ending at one end in an axial groove opening in the fuel intake chamber, characterized in that two channels (14 ' ) above are provided and that the aforementioned groove (9 ') associated with each channel extends parallel to the edge of the upper surface (15) of the piston and opens into one of said vertical grooves (8). 7.- Pompe d'injection selon l'une des revendications 2 à 6,
caractérisée en ce que l'arête supérieure de la gorge (9, 9') d'interruption du refoulement précitée est configurée au moins partiellement en rampe hélicoïdale pour permettre la variation de l'instant d'interruption dudit refoulement.7.- injection pump according to one of claims 2 to 6,
characterized in that the upper edge of the groove (9, 9 ') for interrupting the aforementioned delivery is configured at least partially in a helical ramp to allow the variation of the instant of interruption of said delivery. 8.- Pompe selon l'une des revendications 2 à 7, caractérisée en ce que l'arête inférieure de la gorge (9, 9') d'interruption du refoulement précitée est configurée, au moins partiellement en rampe hélicoïdale , pour permettre la variation du début du refoulement d'injection principale.8.- Pump according to one of claims 2 to 7, characterized in that the lower edge of the groove (9, 9 ') for interrupting the above-mentioned delivery is configured, at least partially in a helical ramp, to allow variation of the start of the main injection delivery. 9.- Pompe d'injection selon l'une des revendications précédentes,
caractérisée en ce qu'elle comprend un dispositif accumulateur de combustible refoulé par ledit piston (2) et adapté pour permettre la variation du début du refoulement de préinjection sans influencer le début du refoulement d'injection principale.9.- Injection pump according to one of the preceding claims,
characterized in that it comprises a fuel accumulator device discharged by said piston (2) and adapted to allow the variation of the start of the pre-injection delivery without influencing the start of the main injection delivery. 10.- Pompe d'injection selon la revendication 9, caractérisée en ce que le dispositif accumulateur comprend une chambre accumulatrice (16) qui est en communication permanente avec la chambre d'admission (3) précitée et a un volume variable par un piston (17) monté mobile dans ladite chambre accumulatrice (16) à l'encontre d'un ressort de rappel (18), la course dudit piston (17) étant limitée par une butée formant siège (22) étancheyet en ce que le piston (17) est maintenu sur son siège (22) pendant l'interruption du refoulement en raison de la mise en communication de la gorge d'interruption (9, 9') précitée et des canaux (14,14') supplémentaires précités.10.- Injection pump according to claim 9, characterized in that the accumulator device comprises an accumulator chamber (16) which is in permanent communication with the aforementioned intake chamber (3) and has a variable volume by a piston ( 17) mounted movably in said accumulator chamber (16) against a return spring (18), the stroke of said piston (17) being limited by a stop forming a seat (22) airtight and in that the piston (17 ) is held in its seat (22) during the interruption of the discharge due to the communication of the abovementioned interruption groove (9, 9 ') and the aforementioned additional channels (14, 14'). 11.- Pompe d'injection selon la revendication 10, caractérisée en ce que la partie de la chambre accumulatrice (16) précitée contenant le ressort de rappel (18) précité est en communication avec le volume duquel partent les orifices d'arrivée (4) de combustible précités.11.- Injection pump according to claim 10, characterized in that the part of the aforementioned accumulator chamber (16) containing the aforementioned return spring (18) is in communication with the volume from which the inlet orifices (4 ) of the aforementioned fuel. 12.- Pompe d'injection selon la revendication 10 ou 11, caractérisée en ce que la longueur de la course du piston (17) situé dans la chambre accumulatrice (16) est variable par variation de la position de la butée (22) précitée.12.- injection pump according to claim 10 or 11, characterized in that the length of the stroke of the piston (17) located in the accumulator chamber (16) is variable by varying the position of the abovementioned stop (22). 13.- Pompe d'injection selon la revendication 12, caractérisée en ce que la position de la butée (22) précitée est variable depuis l'extérieur de la pompe.13.- Injection pump according to claim 12, characterized in that the position of the abovementioned stop (22) is variable from outside the pump. 14.- Pompe d'injection selon la revendication 11, caractérisée en ce que le piston a sensiblement le même diamètre que la chambre accumulatrice, qu'une tige (24) est fixée à la face arrière du piston (17)précité et que l'extrémité libre de ladite tige (24) est amenée hors de la structure de la pompe pour déterminer la longueur de la course du piston.14.- Injection pump according to claim 11, characterized in that the piston has substantially the same diameter as the accumulator chamber, that a rod (24) is fixed to the rear face of the piston (17) mentioned above and that l the free end of said rod (24) is brought out of the pump structure to determine the length of the piston stroke.
EP80400720A 1979-05-28 1980-05-22 Injection pump for internal-combustion engine Expired EP0020249B1 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
FR7913486 1979-05-28
FR7913486A FR2457987A1 (en) 1979-05-28 1979-05-28 Fuel pump for internal combustion engine - pre-injects small quantity of fuel through small secondary inlet port at beginning of each stroke
FR8011046A FR2482669A2 (en) 1979-05-28 1980-05-16 IMPROVEMENT TO INJECTION PUMP FOR INTERNAL COMBUSTION ENGINE
FR8011046 1980-05-16

Publications (2)

Publication Number Publication Date
EP0020249A1 true EP0020249A1 (en) 1980-12-10
EP0020249B1 EP0020249B1 (en) 1984-08-22

Family

ID=26221181

Family Applications (1)

Application Number Title Priority Date Filing Date
EP80400720A Expired EP0020249B1 (en) 1979-05-28 1980-05-22 Injection pump for internal-combustion engine

Country Status (12)

Country Link
US (1) US4426198A (en)
EP (1) EP0020249B1 (en)
JP (1) JPS55161958A (en)
KR (1) KR840001289B1 (en)
AU (1) AU544751B2 (en)
CS (1) CS243455B2 (en)
DD (1) DD151205A5 (en)
DE (1) DE3069004D1 (en)
ES (1) ES491946A0 (en)
FR (1) FR2482669A2 (en)
PL (1) PL136603B1 (en)
YU (1) YU42508B (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2504203A1 (en) * 1981-04-16 1982-10-22 Semt INJECTION PUMP FOR INTERNAL COMBUSTION ENGINE COMPRISING A DEVICE FOR ADJUSTING THE INJECTION FUEL DELIVERY TIME
FR2582355A1 (en) * 1985-05-24 1986-11-28 Orbital Eng Pty IMPROVEMENTS IN FUEL SUPPLY APPARATUS OF INTERNAL COMBUSTION ENGINES
FR2612569A1 (en) * 1987-03-21 1988-09-23 Volkswagen Ag Injector/pump
FR2630166A1 (en) * 1988-04-18 1989-10-20 Hatz Motoren FUEL INJECTION PUMP FOR PRE-INJECTION INTERNAL COMBUSTION ENGINES
EP0363088A1 (en) * 1988-10-06 1990-04-11 LUCAS INDUSTRIES public limited company Pump
FR2649758A1 (en) * 1989-07-14 1991-01-18 Daimler Benz Ag INCLINED CHANGING FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
PL131829B1 (en) * 1982-01-18 1985-01-31 Wyzsza Szkola Inzynierska Gagari Surgical strut for treating spine anomalies
DE3307828A1 (en) * 1983-03-05 1984-09-06 Robert Bosch Gmbh, 7000 Stuttgart FUEL INJECTION DEVICE FOR INTERNAL COMBUSTION ENGINES
DE3307826A1 (en) * 1983-03-05 1984-09-06 Robert Bosch Gmbh, 7000 Stuttgart FUEL INJECTION DEVICE FOR INTERNAL COMBUSTION ENGINES
DE3330774A1 (en) * 1983-08-26 1985-03-14 Robert Bosch Gmbh, 7000 Stuttgart FUEL INJECTION DEVICE WITH PRIMARY AND MAIN INJECTION IN INTERNAL COMBUSTION ENGINES
DE3424989C2 (en) * 1984-07-06 1994-09-29 Bosch Gmbh Robert Fuel injection pump for internal combustion engines
JPS6137462U (en) * 1984-08-09 1986-03-08 株式会社ボッシュオートモーティブ システム fuel injection pump
CH667899A5 (en) * 1985-10-18 1988-11-15 Sulzer Ag FUEL INJECTION DEVICE FOR A DIESEL INTERNAL COMBUSTION ENGINE.
CH671073A5 (en) * 1986-09-09 1989-07-31 Nova Werke Ag
DE4029159A1 (en) * 1990-01-03 1991-07-04 Bosch Gmbh Robert FUEL INJECTION DEVICE FOR INJECTION COMBUSTION ENGINES
DE4022226A1 (en) * 1990-07-12 1992-01-16 Man Nutzfahrzeuge Ag FUEL INJECTION DEVICE FOR AIR COMPRESSING INTERNAL COMBUSTION ENGINES
US5133645A (en) * 1990-07-16 1992-07-28 Diesel Technology Corporation Common rail fuel injection system
US5230613A (en) * 1990-07-16 1993-07-27 Diesel Technology Company Common rail fuel injection system
DE4105168A1 (en) * 1990-12-10 1992-06-11 Man Nutzfahrzeuge Ag INJECTION SYSTEM FOR AIR COMPRESSING ENGINES
DE4106813A1 (en) * 1991-03-04 1992-09-10 Bosch Gmbh Robert FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES
DE4137072A1 (en) * 1991-11-12 1993-05-13 Bosch Gmbh Robert FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES
EP0962648A1 (en) * 1998-06-04 1999-12-08 Wolfgang Dr. Heimberg Fuel injection apparatus
US6799602B2 (en) * 2001-12-28 2004-10-05 Visteon Global Technologies, Inc. Combination fitting
EP1612394B1 (en) * 2004-06-30 2011-04-27 C.R.F. Società Consortile per Azioni Fuel injection system for an internal combustion engine with common rail
KR100992227B1 (en) * 2008-10-27 2010-11-05 현대중공업 주식회사 Prevention device of cavitation erosion damage in the fuel injection pump of the diesel engine

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE572711C (en) * 1931-07-03 1933-03-22 Maschf Augsburg Nuernberg Ag Fuel pump
DE585014C (en) * 1932-06-22 1933-09-27 Robert Bosch Akt Ges Injection pump for internal combustion engines with pre-injection
FR838688A (en) * 1937-11-25 1939-03-13 Andre Citroe N Fractional injection injection device
DE689545C (en) * 1933-02-17 1940-03-27 Bosch Gmbh Robert ff quantity for vehicle diesel engines
US2237347A (en) * 1938-11-30 1941-04-08 Borg Warner Pump control
GB571485A (en) * 1942-09-16 1945-08-27 Bendix Aviat Corp Improvements in or relating to fuel injection apparatus
GB641575A (en) * 1948-01-03 1950-08-16 Cav Ltd Improvements relating to liquid fuel injection pumps
FR1037219A (en) * 1950-05-24 1953-09-15 Cav Ltd Fuel injection pump for internal combustion engines
DE923400C (en) * 1941-04-03 1955-02-10 Versuchsanstalt Fuer Luftfahrt Regulation of the fuel quantity of internal combustion engines according to the Otto method with split injection
US2713310A (en) * 1951-11-20 1955-07-19 Cav Ltd Liquid fuel injection pumps
US2810375A (en) * 1953-04-13 1957-10-22 Nordberg Manufacturing Co Injection pump for internal combustion engines
US3792692A (en) * 1972-03-22 1974-02-19 Teledyne Ind Fuel injection device
DE2501764A1 (en) * 1975-01-17 1976-07-22 Guenther Kuske Diesel engine fuel injection pump - has plunger with intermediate groove to produce pre-injection before main injection

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5221639Y2 (en) * 1973-07-18 1977-05-18
JPS50157721A (en) * 1974-06-10 1975-12-19
JPS525391Y2 (en) * 1974-10-03 1977-02-03

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE572711C (en) * 1931-07-03 1933-03-22 Maschf Augsburg Nuernberg Ag Fuel pump
DE585014C (en) * 1932-06-22 1933-09-27 Robert Bosch Akt Ges Injection pump for internal combustion engines with pre-injection
DE689545C (en) * 1933-02-17 1940-03-27 Bosch Gmbh Robert ff quantity for vehicle diesel engines
FR838688A (en) * 1937-11-25 1939-03-13 Andre Citroe N Fractional injection injection device
US2237347A (en) * 1938-11-30 1941-04-08 Borg Warner Pump control
DE923400C (en) * 1941-04-03 1955-02-10 Versuchsanstalt Fuer Luftfahrt Regulation of the fuel quantity of internal combustion engines according to the Otto method with split injection
GB571485A (en) * 1942-09-16 1945-08-27 Bendix Aviat Corp Improvements in or relating to fuel injection apparatus
GB641575A (en) * 1948-01-03 1950-08-16 Cav Ltd Improvements relating to liquid fuel injection pumps
FR1037219A (en) * 1950-05-24 1953-09-15 Cav Ltd Fuel injection pump for internal combustion engines
US2713310A (en) * 1951-11-20 1955-07-19 Cav Ltd Liquid fuel injection pumps
US2810375A (en) * 1953-04-13 1957-10-22 Nordberg Manufacturing Co Injection pump for internal combustion engines
US3792692A (en) * 1972-03-22 1974-02-19 Teledyne Ind Fuel injection device
DE2501764A1 (en) * 1975-01-17 1976-07-22 Guenther Kuske Diesel engine fuel injection pump - has plunger with intermediate groove to produce pre-injection before main injection

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2504203A1 (en) * 1981-04-16 1982-10-22 Semt INJECTION PUMP FOR INTERNAL COMBUSTION ENGINE COMPRISING A DEVICE FOR ADJUSTING THE INJECTION FUEL DELIVERY TIME
EP0063523A1 (en) * 1981-04-16 1982-10-27 Societe D'etudes De Machines Thermiques S.E.M.T. Injection pump for an internal-combustion engine comprising a mechanism for controlling the start of the fuel injection delivery
US4705006A (en) * 1981-04-16 1987-11-10 Dirk Bastenhof Fuel injection pump for an internal combustion engine comprising a device for adjusting the instant of injection fuel delivery
FR2582355A1 (en) * 1985-05-24 1986-11-28 Orbital Eng Pty IMPROVEMENTS IN FUEL SUPPLY APPARATUS OF INTERNAL COMBUSTION ENGINES
FR2612569A1 (en) * 1987-03-21 1988-09-23 Volkswagen Ag Injector/pump
FR2630166A1 (en) * 1988-04-18 1989-10-20 Hatz Motoren FUEL INJECTION PUMP FOR PRE-INJECTION INTERNAL COMBUSTION ENGINES
EP0363088A1 (en) * 1988-10-06 1990-04-11 LUCAS INDUSTRIES public limited company Pump
FR2649758A1 (en) * 1989-07-14 1991-01-18 Daimler Benz Ag INCLINED CHANGING FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES
GB2235955A (en) * 1989-07-14 1991-03-20 Daimler Benz Ag Sloping-edge-controlled fuel injection pump for internal combustion engines
GB2235955B (en) * 1989-07-14 1993-08-04 Daimler Benz Ag Sloping-edge-controlled fuel injection pump for internal combustion engines

Also Published As

Publication number Publication date
PL136603B1 (en) 1986-03-31
CS375080A2 (en) 1985-08-15
AU5882880A (en) 1980-12-04
DD151205A5 (en) 1981-10-08
JPS55161958A (en) 1980-12-16
ES8103592A1 (en) 1981-03-16
US4426198A (en) 1984-01-17
DE3069004D1 (en) 1984-09-27
EP0020249B1 (en) 1984-08-22
YU142580A (en) 1983-01-21
JPH0214542B2 (en) 1990-04-09
YU42508B (en) 1988-10-31
ES491946A0 (en) 1981-03-16
CS243455B2 (en) 1986-06-12
PL224562A1 (en) 1981-02-27
KR830003002A (en) 1983-05-31
KR840001289B1 (en) 1984-09-07
FR2482669B2 (en) 1984-07-06
FR2482669A2 (en) 1981-11-20
AU544751B2 (en) 1985-06-13

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