| EP0775821A1 | 1997-05-28 | |||
| US5875743A | 1999-03-02 | |||
| US4217871A | 1980-08-19 | |||
| US2640422A | 1953-06-02 | |||
| EP0420642A1 | 1991-04-03 | |||
| US3812830A | 1974-05-28 |
PATENT ABSTRACTS OF JAPAN vol. 1995, no. 09 31 October 1995 (1995-10-31)
| 1. | 1) System at direct injection and manipulation of it. This systems are characterised by having more than one injector per cylinder. |
| 2. | Injection system as per claim 1) where the injectors peep out in the combustion chamber. |
| 3. | Injection system as per claims 1) where one injector peeps out in the combustion chamber head whilst the other one is placed on the suction conduit. |
| 4. | Injection system as pre claims 1) where one injector peeps out in the principal combustion chamber whilst the other one peeps out in a side chamber connected to the main combustion chamber. |
| 5. | Injection system as per claims 1) where the injectors are placed in a side chamber connected to the main combustion chamber. |
| 6. | The systems as per claims 1), 2), 3), 4) and 5) could be composed by more than two injectors, which could be different from each other or could constitute groups of injectors. |
| 7. | Injection systems constituted from a mix of the systems described previously. |
| 8. | The injection law of the injection systems, as claims 1), 2), 3), 4), 5), 6), 7) is the sum of each injection law relating to each injector or groups of injectors. |
| 9. | Injection system as per claims 1), 2), 4), 5), 6), 7) and 8) (referring, for simplicity, only to the system with two injectors), where the injection can be manipulated in such a way that the main injection, the preinjection (s) and possibly the postinjection happen in an alternating way; in other words, each injector performs a full injection once every two cycles. |
| 10. | Injection system as per claim 9) where both the main injection and the preinjection (s) happen in an alternating way, with the difference that the preinjection (s) of an injector happens during the same cycle in which happens the full injection cycle of the other ; in other words also the injector which during a given cycle should be resting, may participate by performing some preinjections or mini injections. |
| 11. | Injection system as per claims 9) and 10) in which the injectors are more than two or more than two groups. In this instance, each injection will follow each other with a frequency depending on the number of the injectors or on the number of the groups of the injectors. |
| 12. | Injection system as per claims 9), 10) and 11) where the preinjection (s) relating to one injector, or to a group of injectors, is not constrained from the main injection (s) of the other injector (s) and vice versa. |
| 13. | Injection system as per claims 1), 2), 3), 4), 5), 6) and 7) where the preinjection relating to one injector, or to a group of injectors, can be overlapped to the main injection of the other injector (s). |
| 14. | Injection system as per claims 3), 6) and 7) where the injection (s) and/or the pre injection (s) of the injector (s) placed on the suction conduit are preferably performed during the aspiration phase, whilst the injectors which directly peep out in the combustion chamber, follow one of the injection laws described in claims 8), 9), 10), 11), 12) and 13). |
| 15. | Injection system as per claims 1), 2), 4), 5), 6) and 7) where the manipulation of the direct injection for the engines at spark plug ignition gasoline engines), would allow one of the two, or both the injectors, to inject the fuel during the aspiration and compression phases and that both, or only one of the injectors, perform a postinjection slightly before or simultaneously to the ignition spark. |
| 16. | Injection system as per claims 1), 2), 4), 5), 6) and 7), where the management of the direct injection for the gasoline engines, would allow one of the injectors to inject the fuel during the aspiration and compression phases, whilst the other injector would inject a given amount of fuel, in proximity of the sparking plug, before or simultaneously to the ignition spark. This latter injector could also inject during the aspiration and compression phases. |
| 17. | Injection system as per claims 1), 3), 4), 5), 6) and 7), where the management of the injection for the gasoline engines, allows the injector placed on the suction conduit inject a certain amount of fuel and the injector which peep out in the combustion chamber and/or in the prechamber inject the remaining part of the fuel during the aspiration and compression phases and/or, in proximity of the sparking plug, before or simultaneously to the moment of the ignition spark. |
| 18. | Injection system as per claim 17) with the difference of having more than one injector which peep out in the combustion chamber and/or in the prechamber as per claims 1), 2), 4), 6) and 7), where the management of the injectors is as per claim 16) and/or more injectors placed on the suction conduit. |
| 19. | The electronic manipulation of the injectors allows the management of the engine, with one of the systems described before or with a combination of them, going from one management system to another with continuity and in function of the specific parameters of instantaneous working of the engine, detected with appropriate sensors; in other words, the same engine can be managed by one of the above mentioned systems of managing and then go to another managing system, as soon as the motion conditions change, and managing the change from one system to another in the most appropriate way. AMENDED CLAIMS [received by the International Bureau on 8 February 2001 (08. 02.; original claims 119 replaced by new claims 114 (2 pages)] 1) System at direct injection and manipulation of it. This systems are characterised by having a fuel pump that give pressure to a circuit of pipes that give fuel two or more electroinjectors per cylinder where peep out in the combustion chamber ; the pressure in the circuit and the electroinjectors are handled by an electronic control unit. |
| 20. | Injection system as per claims 1) where more than one electroinjector peeps out in the combustion chamber head whilst an other one is placed on the suction conduit. |
| 21. | The systems as per claims 1), and 2) could be composed by more than two electro injectors, which could be different from each other or could constitute groups of electro injectors. |
| 22. | Injection systems constituted from a mix of the systems described previously. |
| 23. | Injection system as per claims 1), 3) and 4) (referring, for simplicity, only to the system with two electroinjectors), where the injection can be manipulated in such a way that the main injection, the preinjection (s) and possibly the postinjection happen in an alternating way; in other words, each electroinjector performs a full injection once every two cycles. |
| 24. | Injection system as per claim 5) where both the main injection and the prvinjection (s) happen in an alternating way, with the difference that the preinjection (s) of an electro injector happens during the same cycle in which happens the full injection cycle of the other, in other words also the electroinjector which during a given cycle should be resting, may participate by performing some preinjections or mini injections. |
| 25. | Injection system as per claims 5) and 6) in which the electroinjectors are more than two or more than two groups. In this instance, each injection will follow each other with a frequency depending on the number of the electroinjectors or on the number of the groups of the electroinjectors. |
| 26. | Injection system as per claims 1), 2), 3), and 4) where the preinjection relating to one electroinjector, or to a group of electroinjectors, can be overlapped to the main injection of the other electroinjector (s). |
| 27. | Injection system as per claims 2), 3) and 4) where the injection (s) and/or the pre injection (s) of the electroinjector (s) placed on the suction conduit are preferably performed during the aspiration phase, whilst the electroinjectors which directly peep out in the combustion chamber, follow one of the injection laws described in claims 5), 6), 7), and 8). |
| 28. | Injection system as per claims 3) and 4) where the manipulation of the direct injection for the engines at spark plug ignition gasoline engines), would allow one of the two, or both the electroinjectors, to inject the fuel during the aspiration and compression phases and that both, or only one of the electroinjectors, perform a postinjection slightly before or simultaneously to the ignition spark. |
| 29. | Injection system as per claims 1), 3) and 4), where the management of the direct injection for the gasoline engines, would allow one of the electroinjectors to inject the fuel during the aspiration and compression phases, whilst the other electroinjector would inject a given amount of fuel, in proximity of the sparking plug, before or simultaneously to the ignition spark. This latter electroinjector could also inject during the aspiration and compression phases. |
| 30. | Injection system as per claims 1), 2), 3), and 4), where the management of the injection for the gasoline engines, allows the electroinjector placed on the suction conduit inject a certain amount of fuel and the electroinjector which peep out in the combustion chamber and/or in the prechamber inject the remaining part of the fuel during the aspiration and compression phases and/or, in proximity of the sparking plug, before or simultaneously to the moment of the ignition spark. |
| 31. | Injection system as per claim 12) with the difference of having more than one electro injector which peep out in the combustion chamber and/or in the prechamber as per claims 1), 3) and 4), where the management of the electroinjectors is as per claim 11) and/or more electroinjectors placed on the suction conduit. |
| 32. | The electronic manipulation of the electroinjectors allows the management of the engine, with one of the systems described before or with a combination of them, going from one management system to another with continuity and in function of the specific parameters of instantaneous working of the engine, detected with appropriate sensors; in other words, the same engine can be managed by one of the above mentioned systems of managing and then go to another managing system, as soon as the motion conditions change, and managing the change from one system to another in the most appropriate way. |
Due to the possibility of more degrees of freedom, the above system allows a better optimisation of the injection process of the fuel inside the combustion chamber, compared to the present systems. This will benefit the combustion efficiency and the quality of the exhaust gasses.
The above system offers a variety of possibilities and applications. The following will illustrate some examples of the above, bearing in mind that there are many other more possible combinations.
DESCRIPTION The multi-injection system is composed by any injection system with the peculiarity of having two or more injectors which, depending on the needs, may also be different from each other.
The mechanical management or preferably, electronic management of the injectors allows the possibility of degrees of freedom which, in the injection and pre-injection laws, are far more superior to the mono-injection system.
The following, although we only write about two injectors, is also applicable to systems utilising more than two injectors.
SYSTEM APPLIED TO DIESEL ENGINES AT DIRECT INJECTION It is well known that, due to the different needs of the engines, in relation to specific parameters such as load, rotation speed, temperatures, pressures etc., it is difficult to manage the pre-injections of the fuel in relation to the main injection. Also, combustion is more efficient when the fuel is injected in the combustion chamber in a fine and homogeneous way.
The proposed system allows to free the pre-injection (s) from the main injection because it is possible to manage the two or more injectors in an independent way. This allows the pre- injection relating to one injector to be performed independently from the main injection of the other injector. For example, the pre-injection relating to an injector can be performed before or, possibly the end of it can happen at the same time as the main injection of the other injector.
The main injection, as it can be performed with more injectors, allows a better mixing of the fuel with the air. This is because each injector has to inject a reduced amount of fuel, with consequent finer pulverize, because the points of injection are placed in different positions,
and because the laws regulating each injection can differ between each other (start of the injection, quantity of injected fuel etc.). In addition, the above allows the usage of exercise pressures which are far much lower with consequent reduction of the costs and better performance of the injection system.
Table 1/2 shows an example of what could be an injection law obtained with two injectors and in which the dotted lines represent the injection laws of the two injectors, respectively, whilst the continuous line represents the sum of each injection; Fig. 1 shows that the pre-injection of an injector is simultaneous to the main injection of the other injector and, it is also possible to see that one of the injectors only performs the pre-injection; Fig. 2 shows each law of injection and the final resulting injection (summation of the two injections).
An additional aim which can be achieved with the double injector could be to allow the Diesel engines to reach, compatibly with the inertia forces, rotation speeds which are sensibly higher compared to the traditional systems; this is possibly if the two injectors work in an alternative way, this is to say that each injector injects its own amount of fuel once every four revolutions of the crank. Therefore, the rotation speed of the engine, for the injection system, could also be double compared to the maximal rotation speed which can be reached with the current systems.
From the above, it is obvious that the multi-injection proposal allows a wide freedom in the choice of the criteria managing the the system. It is also obvious that it is possible, when the engine is functioning, to switch from one management criterion (oppure-way of management) to another, managing the switch in the most appropriate way ; this is also applicable to the management systems described below.
SYSTEM APPLIED TO GASOLINE ENGINES In the evolution of the gasoline engines, the research is focused on the engines at direct injection. One of the major problems to overcome is the difficulty of obtaining a mixture which is both homogeneous and uniformly distributed.
The application of the double injector may be highly beneficial to the system and can be formulated in at least two ways: -First system-to position the injectors in such a way that the pulverizer peeps out directly in the combustion chamber.
-Second system-to ensure that one injector peep out in the combustion chamber, whilst the other injector on the suction conduit.
The advantages which can be reached using the first system are that the injectors, being two
or more, better homogenise the fuel load.
One of the two injectors could have the task of injecting a given amount of fuel in the proximity of the area where the combustion starts and shortly before the ignition spark. In this way, around the sparking plug there will be a mixture which is sufficiently carburetted. This would allow also the usage of lean mixture because the injection performed, in the proximity of the sparking plug, makes rich the mixture only in that area, thus helping the start of the combustion.
It is also possible to think of performing a small injection during the first phase of the combustion so that the particles of the fuel which will be vaporized during the crossing of the combusted area, will start micro-combustions in areas which are not yet combusted and which are far away from the front of the flame. The result would be the increase of the speed of the combustion and the reduction of the detonation problem.
An example of how one of the possible injection laws could be, is described in Fig. 3 Table 2/2, where an injector (continuous line) performs both the injection during the suction phase and the post-injection (this latter could also not be performed at all or, be performed by another injector), whilst another injector performs the pre-injection possibly in proximity of the candle.
A way of using the second system above could be to use the injector placed on the suction conduit for the formation of a very lean (but homogeneous) mixture whilst the injector placed on the cylinder head could have the task to enrich the mixture in the starting area (around the sparking plug) and eventually of performing a post-injection (this latter task may also be performed by an additional injector).
Figure 3 Table 2/2 shows an injection law where the injector performs an injection in the suction conduit (continuous line) whilst another injector, placed on the cylinder head, performs the pre-injection (dotted line); the above Figure also shows a post-injection (dotted- point line) which could be performed both by the same injector (which has just performed the pre-injection) or by another injector.
Another system could be that-of having a given amount of fuel injected by one injector, placed in some sort of pre-chamber where the candle is placed, whilst another injector performs the injection in the combustion chamber.
Both the systems could be used by both the four stroke and the two stroke engines.
Next Patent: FUEL INJECTION VALVE FOR INTERNAL COMBUSTION ENGINES AND A METHOD FOR PRODUCING SAME