DE112020000741T5 - Fuel injection system - Google Patents

Abstract

A fuel injection system includes (i) a plurality of injectors including at least two injectors (40, 50), the plurality of injectors configured to inject gaseous fuel into an engine (20), (ii) a fuel tank (30) that configures is to store gas fuel, and (iii) a delivery line (312, 313) configured to deliver the gas fuel from the fuel tank to each of the plurality of injectors. The fuel injection system further includes (i) a wear amount estimation unit (72) configured to estimate a wear amount of each of the plurality of injectors, and (ii) a determination unit (73) configured based on the wear amount of each of the plurality of injectors estimated by the wear amount estimating unit, to determine which of the plurality of injectors is preferentially operated.

Description

Cross reference

This application is based on and claims priority from Japanese Patent Application No. 2019-020536 , filed February 7, 2019, the entire disclosure of which is incorporated herein by reference.

Technical area

The present disclosure relates to a fuel injection system.

background

There is known a vehicle fuel injection system described in Patent Literature 1 below. In the fuel injection system described in Patent Literature 1, compressed natural gas (hereinafter abbreviated as “CNG”) is used as fuel for an internal combustion engine, and the CNG fuel is injected into the internal combustion engine through an injector. In the fuel injection system described in Patent Literature 1, when the fuel temperature difference between the cylinders of an internal combustion engine is within a predetermined allowable range during stratified combustion, the fuel injection control of the internal combustion engine is carried out by correcting the fuel injection amount and the fuel injection timing based on the average temperature and pressure of the Running fuel. Further, when the fuel temperature difference between the cylinders is outside the predetermined allowable range during stratified combustion, this fuel injection system switches to homogeneous combustion, corrects the injection amount based on the average temperature and pressure of the fuel, and controls the fuel injection of the internal combustion engine.

Prior art literature

Patent literature

Patent Literature 1: JP 2005-240581 A

Summary of the invention

When liquid fuel is used as the fuel for the internal combustion engine, the injector can be lubricated with the liquid fuel at interfaces. The fuel injection system described in Patent Literature 1 uses a gas fuel such as CNG fuel as fuel for the internal combustion engine. In this case, it becomes difficult to perform interface lubrication of the injector with fuel. Therefore, in a fuel injection system using gas fuel, wear is likely to be promoted in the sliding portion of the injector. Hence, there is room for improvement in terms of injector longevity.

It is an object of the present disclosure to provide a fuel injection system that can improve the longevity of an injector that injects gas fuel.

According to an example of the present disclosure, there is provided a fuel injection system including: (i) a plurality of injectors including at least two injectors, the plurality of injectors configured to inject gaseous fuel into an engine, (ii) a fuel tank that configures is to store the gas fuel, and (iii) a delivery line configured to supply the gas fuel from the fuel tank to each of the plurality of injectors. The fuel injection system further includes (i) a wear amount estimating unit and (ii) a determining unit. The wear amount estimating unit is configured to estimate a wear amount of each of the plurality of injectors. The determination unit is configured to determine which of the plurality of injectors is preferentially operated based on the amount of wear of each of the plurality of injectors estimated by the amount of wear estimation unit.

According to this configuration, it is possible to preferably operate a more suitable injector according to the amount of wear of a plurality of injectors. Therefore, the longevity of the injector that injects gas fuel can be improved.

Figure list

• 1 Fig. 13 is a diagram schematically showing a configuration of a fuel injection system according to a first embodiment;
• 2 Fig. 13 is a block diagram showing an electrical configuration of the fuel injection system according to the first embodiment;
• 3 Fig. 13 is a flowchart showing a processing procedure performed by a control device according to the first embodiment;
• 4th Fig. 13 is a flowchart showing a flow of processing performed by a control device according to a second embodiment;
• 5 Fig. 13 is a flowchart showing a processing sequence carried out by a Control device is performed according to a third embodiment;
• 6th Fig. 13 is a flowchart showing a flow of processing performed by a control device according to a fourth embodiment;
• 7th Fig. 13 is a flowchart showing a processing procedure performed by a control device according to a fifth embodiment;
• 8th Fig. 13 is a flowchart showing a flow of processing performed by a control device according to a sixth embodiment;
• 9 Fig. 13 is a flowchart showing a flow of processing performed by a control device according to a first modified example of the sixth embodiment;
• 10 Fig. 13 is a flowchart showing a flow of processing performed by a control device according to a second modified example of the sixth embodiment;
• 11 Fig. 13 is a flowchart showing a processing procedure performed by a control device according to a third modified example of the sixth embodiment;
• 12th Fig. 13 is a flowchart showing a processing procedure performed by a control device according to a fourth modified example of the sixth embodiment;
• 13th Fig. 13 is a flowchart showing a processing procedure performed by a control device according to a seventh embodiment;
• 14th Fig. 13 is a flowchart showing a flow of processing performed by a control device according to an eighth embodiment; and
• 15th Fig. 13 is a flowchart showing a flow of processing performed by a control device according to a ninth embodiment.

Embodiments for carrying out the invention

In the following, the embodiments of a fuel injection system will be described with reference to the drawings. For a better understanding, the same reference symbols have been used, where possible, for the same constituent elements in the drawings, redundant explanations being omitted.

First embodiment

First is a fuel injection system 10 according to a first embodiment shown in 1 is shown, described. The fuel injection system 10 , this in 1 Shown is a system for injecting fuel into an internal combustion engine 20th of a vehicle. As fuel for the internal combustion engine 20th In the present embodiment, a gas fuel such as CNG (compressed natural gas) is used. It should be noted that 1 just a single cylinder 21 from the plurality of cylinders used in the internal combustion engine 20th are provided shows. The fuel injection system 10 contains a fuel tank 30th , an orifice injection injector 40 and a direct injection injector 50 .

High pressure gas fuel is in the fuel tank 30th saved. A fuel line 31 is with the fuel tank 30th tied together. The fuel line 31 is from a middle section in a first branch line 310 and a second branch line 311 branched off. A first delivery line 312 is with the top of the first branch line 310 tied together. A second delivery line 313 is with the top of the second branch line 311 tied together. The high pressure gas fuel that is in the fuel tank 30th is stored, becomes the first delivery line 312 and the second delivery line 313 via the fuel line 31 fed. The first delivery line 312 leads gaseous fuel to the port injection injector 40 to that in each cylinder 21 of the internal combustion engine 20th is provided. The second delivery line 313 leads gas fuel to the direct injection injector 50 to that in each cylinder 21 of the internal combustion engine 20th is provided.

The fuel line 31 is equipped with a fuel shut-off valve 32 and a regulating device 33 intended. Further is the first branch line 310 with a regulating device 34 intended. The fuel shut-off valve 32 can switch between supplying and shutting off gas fuel from the fuel tank 30th to the delivery lines 312 and 313 switch by opening and closing. The regulating device 33 can control the pressure of the gas fuel coming from the fuel tank 30th to the second delivery line 313 adjusted by changing its opening degree. The regulating device 34 can control the pressure of the gas fuel coming from the fuel tank 30th to the first delivery line 312 adjusted by changing its opening degree.

The port injection injector 40 is in the inlet passage 22nd of the internal combustion engine 20th intended. The port injection injector 40 injects the gas fuel from the first delivery line 312 is supplied into the inlet passage 22nd a. The gas fuel supplied by the port injection injector 40 is injected, is shared with air that is in the inlet passage 22nd flows into the combustion chamber 210 in the cylinder 21 initiated.

The direct injection injector 50 is in the cylinder 21 of the internal combustion engine 20th intended. The direct injection injector 50 injects gas fuel from the second delivery line 313 is fed directly into the combustion chamber 210 in the cylinder 21 a. It should be noted that each cylinder 21 of the internal combustion engine 20th with an orifice injection injector 40 and a direct injection injector 50 is provided. The port injection injector 40 and the direct injection injector 50 are each provided at two corresponding positions set in identical arrangements in each of the plurality of cylinders in the engine.

From the inlet passage 22nd gets air into the combustion chamber 210 from each cylinder 21 of the internal combustion engine 20th via the inlet valve 23 initiated. Furthermore, gas fuel supplied by the port injection injector 40 or the direct injection injector 50 is injected into the combustion chamber 210 initiated. With the internal combustion engine 20th burns the mixture of air and gas fuel in the combustion chamber 210 so that the pistons 211 in every cylinder 21 to move back and fourth. As a result, the driving force of the internal combustion engine 20th can be obtained. The exhaust gas produced by the combustion of the air-fuel mixture in the combustion chamber 210 is generated, becomes the exhaust gas passage 25th of the internal combustion engine 20th via the exhaust valve 24 discharged.

Next is the electrical configuration of the fuel injection system 10 described. As in 1 shown is the fuel tank 30th with a pressure sensor 60 intended. The pressure sensor 60 detects the fuel pressure in the fuel tank 30th , more precisely, the pressure of the gas fuel in the fuel tank 30th is stored and outputs a signal that corresponds to the detected fuel pressure of the fuel tank 30th is equivalent to.

A pressure sensor 61 is on the first delivery line 312 intended. The pressure sensor 61 detects the pressure of the gas fuel inside the first delivery line 312 , in other words, the fuel injection pressure of the port injection injector 40 , and outputs a signal according to the detected gas fuel pressure.

A pressure sensor 62 is in the second delivery line 313 intended. The pressure sensor 62 detects the pressure of the gas fuel inside the second delivery line 313 , in other words, the fuel injection pressure of the direct injection injector 50 , and outputs a signal that corresponds to the detected gas fuel pressure. As in 2 the output signals of the pressure sensors are shown 60 to 62 by the control device 70 recorded. The control device 70 consists mainly of a microcomputer including a CPU, a memory and the like. The control device 70 contains a non-volatile memory 71 for storing different types of information. The control device 70 can provide information on the fuel pressure of the fuel tank 30th , to the fuel injection pressure of the port injection injector 40 and the fuel injection pressure of the direct injection injector 50 based on the output signals from the pressure sensors 60 to 62 gain.

Furthermore, the control device 70 the output signals from sensors installed in the vehicle 63 on. The sensor installed in the vehicle 63 contains a sensor that detects the amount of depression of the accelerator pedal, a crank angle sensor that detects the angle of rotation of the crankshaft of the internal combustion engine 20th detects a flow rate sensor that detects the amount of intake air which is the flow rate of air passing through the intake passage 22nd flows, corresponds to, detects, a temperature sensor that the temperature of the exhaust gas flowing through the exhaust gas passage 25th flows, detected, and a temperature sensor that the temperature of the cooling water of the internal combustion engine 20th recorded.

The control device 70 controls the port injection injector 40 and the direct injection injector 50 from each cylinder 21 based on the various information given by the sensors 60 until 63 are recorded. Accordingly, the fuel injection control becomes to control the fuel injection amount of each cylinder 21 carried out. As an aside, the injectors can 40 and 50 interfaces are not lubricated by the fuel when gas fuel is used as fuel for the internal combustion engine 20th is used. Therefore, the sliding portions of the injectors become 40 and 50 likely to be more worn than compared to a case in which liquid fuel is used as fuel for the internal combustion engine 20th is used. In case the sliding sections of the injectors 40 and 50 are worn out, the fuel injection amount of the injectors varies 40 and 50 so that the fuel injection control cannot be performed correctly.

On the other hand, it shows the amount of wear and tear on each injector 40 , 50 basically shows a correlation with the number Operations of each injector 40 , 50 on. Therefore, in the fuel injection system 10 of the present embodiment, the amount of wear of each injector 40 , 50 based on the number of times each injector has operated 40 , 50 estimated. Then the fuel injection system 10 of the present embodiment from the port injection injector 40 and the direct injection injector 50 preferably the injector is controlled which has the lowest number of operating processes. This improves the longevity of the overall system.

In particular, the control device contains 70 , as in 2 shown, a wear amount estimating unit 72 and a determining unit 73 . The wear amount estimating unit 72 counts the cumulative number of times each injector has operated 40 , 50 as an estimate of the amount of wear of each injector 40 , 50 . The cumulative number of operating processes is the total number of operating processes since the start of the actuation of the injectors 40 and 50 . In particular, the non-volatile memory stores 71 the cumulative number of operations NP of the port injection injector 40 and the cumulative number of operations ND of the direct injection injector 50 . The respective values of the cumulative number of operating processes NP and ND are at the beginning of the actuation of the injectors 40 and 50 set to zero. The wear amount estimating unit 72 increments the value of the cumulative number of operations NP each time the port injection injector 40 is controlled. Further, the wear amount estimating unit increments 72 the value of the cumulative number of operations ND each time the direct injection injector 50 is controlled. The power supply of the control device 70 can be disconnected from the battery after the vehicle is stopped. Even in such a case, it is by storing the cumulative numbers of operations NP and ND in the non-volatile memory 71 possible to maintain the information on the cumulative number of operations NP and ND.

The unit of determination 73 determined based on the cumulative numbers of operations NP and ND of the respective injectors 40 and 50 that are in the non-volatile memory 71 are stored, which of the port injection injector 40 and the direct injection injector 50 is preferably operated. Next is related to 3 the processing sequence carried out by the determining unit 73 is carried out, described in more detail.

As in 3 shown, the determining unit reads 73 than the processing of the step S10 first the maximum numbers of operating processes NPmax and NDmax of the injectors 40 and 50 from non-volatile memory 71 the end. The maximum numbers of operations NPmax and NDmax are the maximum values of the numbers of operations of the injectors 40 and 50 that do not cause an unacceptable change in performance. The maximum numbers of operations NPmax and NDmax are set through experiments and the like and are set in the non-volatile memory in advance 71 saved. When the port injection injector 40 and the direct injection injector 50 have different structures, the maximum numbers of operations NPmax and NDmax can be set to different values. In the present embodiment, each of the maximum numbers of operations NPmax and NDmax corresponds to a predetermined number of operations.

$$\text{NDc}=\text{NDmax}-\text{ND}$$

The unit of determination 73 reads the cumulative numbers of operations NP and ND of the injectors 40 and 50 from non-volatile memory 71 than processing step S11 that on the crotch S10 follows from. The determining unit then calculates 73 than processing step S12 the numbers of permissible operations NPc and NDc of the injectors 40 and 50 based on the following equations f1 and f2. $$\text{NPc}=\text{NPmax}-\text{NP}$$

$$\text{NDc}=\text{NDmax}-\text{ND}$$

As processing step S13 that on the crotch S12 follows, the determining unit determines 73 based on the numbers of allowable operations NPc and NDc of the respective injectors 40 and 50 which from the port injection injector 40 and the direct injection injector 50 is preferably operated. In particular, the determining unit operates 73 preferably the port injection injector 40 when the number of allowable operations NPc of the port injection injector 40 greater than the number of permissible operations NDc of the direct injection injector 50 is. The determining unit also operates 73 preferably the direct injection injector 50 when the number of allowable operations NDc of the direct injection injector 50 greater than the number of allowable operations NPc of the port injection injector 40 is. When the number of allowable operations NPc of the port injection injector 40 and the number of allowable operations NDc of the direct injection injector 50 have the same value, the determining unit determines 73 , either the Port injection injector 40 or direct injection injector 50 to operate.

After performing the processing from step S13 , terminates the determination unit 73 a number of processes that can be found in 3 are shown. The unit of determination 73 performs the processing carried out in 3 is shown for each of the plurality of cylinders 21 of the internal combustion engine 20th individually through.

• (1) Ein geeigneterer Injektor kann vorzugsweise gemäß dem Betrag der Abnutzung von jedem Öffnungseinspritzungs-Injektor 40 und Direkteinspritzungs-Injektor 50 betrieben werden. Daher kann die Langlebigkeit der Injektoren 40 und 50, die Gaskraftstoff einspritzen, verbessert werden.
• (2) Die Abnutzungsbetragsabschätzeinheit 72 schätzt den Abnutzungsbetrag von jedem Injektor 40, 50 basierend auf der kumulativen Anzahl an Betriebsvorgängen NP, ND von jedem Injektor 40, 50. Wie in den vorherigen Gleichungen f1 und f2 gezeigt, berechnet die Bestimmungseinheit 73 einen Subtraktionswert, der durch Subtrahieren der kumulativen Anzahl an Betriebsvorgängen NP, ND von der maximalen Anzahl an Betriebsvorgängen NPmax, NDmax erhalten wird, für jeden der Injektoren 40 und 50. Der Injektor mit dem größten Subtraktionswert wird vorzugsweise betrieben. Gemäß einer solchen Konfiguration wird problemlos und vorzugsweise ein Injektor betrieben, der eine ausreichende Langlebigkeit aufweist.

According to the fuel injection system 10 According to the present embodiment described above, the operations and effects shown in the following, (1) and (2), can be achieved.

• (1) A more suitable injector may preferably be selected according to the amount of wear of each port injection injector 40 and direct injection injector 50 operate. Hence the longevity of the injectors 40 and 50 that inject gas fuel can be improved.
• (2) The wear amount estimating unit 72 estimates the amount of wear and tear on each injector 40 , 50 based on the cumulative number of operations NP, ND of each injector 40 , 50 . As shown in the previous equations f1 and f2, the determining unit calculates 73 a subtraction value obtained by subtracting the cumulative number of operations NP, ND from the maximum number of operations NPmax, NDmax for each of the injectors 40 and 50 . The injector with the greatest subtraction value is preferably operated. According to such a configuration, an injector which has a sufficient longevity is operated without any problems and preferably.

Second embodiment

$$\text{NDr}=\text{ND}/\text{NDmax}$$

Next is a second embodiment of the fuel injection system 10 described. The following are mainly the differences to the fuel injection system 10 of the first embodiment. As in 4th shown, the determining unit calculates 73 In the present embodiment, the ratios of the cumulative operations NPr and NDr of the injectors 40 and 50 based on the following equations f3 and f4 as the processing of step S14 that is on the processing step S11 follows. $$\text{NPr}=\text{NP}/\text{NPmax}$$

$$\text{NDr}=\text{ND}/\text{NDmax}$$

Than processing step S13 that on the crotch S14 follows, the determining unit determines 73 based on the ratios of the cumulative operations NPr and NDr of the injectors 40 and 50 which from the port injection injector 40 and the direct injection injector 50 is preferably operated. In particular, the determining unit operates 73 preferably the port injection injector 40 when the ratio of the cumulative operations NPr of the port injection injector 40 smaller than the ratio of the cumulative operations NDr of the direct injection injector 50 is. The determining unit also operates 73 preferably the direct injection injector 50 when the ratio of the cumulative operations NDr of the direct injection injector 50 smaller than the cumulative operation ratio NPr of the port injection injector 40 is. When the ratio of the cumulative operations NPr of the port injection injector 40 and the cumulative operation ratio NDr of the direct injection injector 50 have the same value, the determining unit determines 73 , either the port injection injector 40 or the direct injection injector 50 to operate.

According to the fuel injection system 10 According to the present embodiment previously described, the operations and effects shown below, (3), can be achieved in place of the operations and effects shown previously in (2).

(3) As shown in the previous equations f3 and f4, the determining unit calculates 73 a division value obtained by dividing the cumulative number of operations NP, ND by the maximum number of operations NPmax, NDmax for each of the injectors 40 and 50 is obtained, and preferably operates the injector with the smallest division value. According to such a configuration, an injector which has a sufficient longevity is operated without any problems and preferably.

Third embodiment

Next will be a third embodiment of the fuel injection system 10 described. The following are mainly the differences to the fuel injection system 10 described in the first embodiment. The unit of determination 73 of the first embodiment performs the preferably operated injector determination processing shown in FIG 3 is shown for each of the plurality of cylinders 21 of the internal combustion engine 20th individually through. On the other hand, the determination unit leads 73 of the present embodiment, the determination processing shown in 3 is shown only for a specific cylinder out of the plurality of cylinders 21 by. At the same time, using the determination result for other cylinders other than the specific cylinder, the preferentially operated injector in the other cylinders is determined.

In particular, as in 5 shown, the determining unit performs 73 than processing step S15 first, the determination processing of the injector that is preferably operated, which is shown in 3 is shown only for a specific cylinder out of the plurality of cylinders 21 of the internal combustion engine 20th by. It is determined for the specific cylinder which of the port injection injector 40 and the direct injection injector 50 is a preferably operated injector.

Next, the determining unit takes into account 73 than processing step S16 the determination result of the injector (ie, the injector that is preferably operated) used in the processing of step S15 has been determined for other cylinders other than the specific cylinder. Accordingly, the preferably operated injector is determined in each of the other cylinders as the injector which is in the same corresponding position set in the identical arrangement as the corresponding position in the identical arrangement of the preferably operated injector used in the specific Cylinder has been determined, is fixed, is provided.

According to the fuel injection system 10 Further, according to the present embodiment described above, the operations and effects shown below, (4), can be achieved.

(4) As the processing of determining the preferentially operated injector for only one specific cylinder among the plurality of cylinders 21 is performed, the determination processing can be simplified. In addition, the same injector is preferably used in each of the plurality of cylinders 21 operated. Therefore, it is possible to experience fluctuations in the life of the injectors 40 and 50 with the multitude of cylinders 21 to suppress.

Fourth embodiment

Next will be a fourth embodiment of the fuel injection system 10 described. The following are mainly the differences to the fuel injection system 10 of the first embodiment. The internal combustion engine 20th , which is a structure that is in 1 shown, the filling efficiency can be increased by injecting gas fuel from the direct injection injector 50 instead of injecting gaseous fuel from the port injection injector 40 improve to the output and fuel economy of the internal combustion engine 20th to improve. Therefore, it is in a situation in which the load on the internal combustion engine 20th is high, desirable, preferably the direct injection injector 50 instead of the port injection injector 40 to operate. Therefore, the determining unit operates 73 In the present embodiment, regardless of the order of magnitude of the numbers of permissible operations NPc and NDc, preferably the direct injection injector 50 when the load on the internal combustion engine 20th is greater than or equal to a predetermined value.

In particular, as in 6th shown, determines the determining unit 73 as a step S20 first whether the load Le of the internal combustion engine 20th is greater than or equal to the predetermined value Lth or not. The load Le of the internal combustion engine 20th is a numerical value of the load condition of the internal combustion engine 20th . The load condition of the internal combustion engine 20th has, for example, a correlation with the speed of the internal combustion engine 20th or the amount of intake air. The unit of determination 73 calculates the load Le of the internal combustion engine 20th from the speed of the combustion engine 20th or the amount of intake air measured by the sensor installed in the vehicle 63 can be detected using a map or the like. The load Le of the internal combustion engine 20th is set so that the value increases when the internal combustion engine 20th goes into the high load state and decreases when the internal combustion engine 20th goes into the low load state.

Assume a case where the determining unit 73 a negative determination in the processing of step S20 takes place, that is, when the load Le of the internal combustion engine 20th is lower than the predetermined value Lth. In such a case, the determining unit performs 73 than processing step S22 performs the determination processing of the injector that is preferably operated, as shown in FIG 3 shown. The determination unit then injects 73 than processing step S23 Gas fuel via the preferably operated injector in the processing of step S22 was determined.

Assume a case where the determining unit 73 an affirmative determination in the processing of step S20 makes, that is, when the load Le of each internal combustion engine 20th is equal to or greater than the predetermined value Lth. In such a case, the determining unit injects 73 than processing step S21 Gas fuel through the direct injection injector 50 a. According to the fuel injection system 10 the present embodiment previously described Furthermore, the processes and effects shown in the following, (5), can be achieved.

(5) Assume a case where, based on the numbers of allowable operations NPc and NDc, the port injection injector 40 should be operated preferentially. Even then, gas fuel is supplied via the direct injection injector 50 regardless of the orders of magnitude of the numbers of allowable operations NPc and NDc injected when the load Le of the internal combustion engine 20th is greater than or equal to the predetermined value Lth. According to such a configuration, the filling efficiency can be increased by injecting gas fuel from the direct injection injector 50 can be improved when the load on the internal combustion engine 20th is high. Therefore, the power consumption and the output of the internal combustion engine 20th be improved.

Fifth embodiment

Next will be a fifth embodiment of the fuel injection system 10 described. The following are mainly the differences to the fuel injection system 10 of the first embodiment. With the direct injection injector 50 gas fuel cannot be injected as long as the injection pressure is higher than the pressure in the combustion chamber 210 is. Further, even if the injection pressure becomes higher than the pressure in the combustion chamber 210 is the difference between the injection pressure and the pressure in the combustion chamber 210 smaller due to the reduction in injection pressure. In such a case, the injection amount of the direct injection injector becomes 50 decreased; therefore, there is a possibility that sufficient gas fuel will not be injected. Therefore, the injection amount of the direct injection injector tends 50 tend to be insufficient when the fuel pressure in the fuel tank is low 30th as a result of the reduction in the fuel tank 30th remaining amount of gas fuel is reduced. As a result, the performance of the internal combustion engine can increase 20th deteriorate and it becomes difficult to get the gas fuel in the fuel tank 30th to use up.

On the other hand, assume a case where the fuel pressure in the fuel tank 30th drops to a level where it becomes difficult to get fuel from the direct injection injector 50 into the combustion chamber 210 inject. Even then, the port injection injector can 40 inject sufficient fuel. Hence the determining unit 73 of the present embodiment preferably configures the port injection injector regardless of the numbers of allowable operations NPc and NDc 40 operate when the fuel pressure in the fuel tank 30th is equal to or less than a predetermined value.

In particular, as in 7th shown, determines the determining unit 73 than processing step S24 first, whether the fuel pressure Pf of the fuel tank 30th by the pressure sensor 60 is detected is equal to or less than a predetermined value Pth or not. Assume a case where the determining unit 73 a negative determination in the processing of step S24 makes, that is, when the fuel pressure Pf of the fuel tank 30th exceeds the predetermined value Pth. In this case, as the processing of step S22 the preferably operated injector determination processing set forth in 3 shown is performed. The determination unit then injects 73 than processing step S23 Gas fuel via the preferably operated injector in the processing of step S22 was determined a.

Assume its case where the determining unit 73 an affirmative determination in the processing of step S24 makes, that is, when the fuel pressure Pf of the fuel tank 30th is equal to or less than the predetermined value Pth. In such a case, the determining unit injects 73 than processing step S31 Gaseous fuel through the port injection injector 40 a. According to the fuel injection system 10 Further, according to the present embodiment described above, the operations and effects shown in the following, (6) can be achieved.

(6) Assume a case where the direct injection injector 50 should preferably be operated based on the numbers of permissible operating processes NPc and NDc. Even in such a case, regardless of the magnitudes of the numbers of allowable operations, NPc and NDc, gas fuel is supplied from the port injection injector 40 injected when the fuel pressure Pf of the fuel tank 30th is less than or equal to the predetermined value Pth. According to such a configuration, gas fuel is supplied from the port injection injector 40 injected when the fuel pressure Pf of the fuel tank 30th is low. The gas fuel in the fuel tank 30th can thus be used up more reliably. As a result, the range of the vehicle can be extended. When gas fuel from the port injection injector 40 is injected, the filling efficiency becomes lower than when gas fuel is injected from the direct injection injector 50 is injected. Therefore, there is a concern that the output of the internal combustion engine 20th can be reduced. To solve this problem, it is effective to reduce the output of the internal combustion engine 20th for example by increasing the gear ratio of the Transmission of the vehicle and by switching the operating point of the internal combustion engine 20th to support the side with high rotation or revolution.

Sixth embodiment

Next will be a sixth embodiment of the fuel injection system 10 described. The following are mainly the differences to the fuel injection system 10 of the first embodiment. When the preferably operated injector determination processing set in 3 is performed constantly, the injector that injects fuel can be performed at every combustion cycle of the internal combustion engine 20th be switched. As a result, there is a possibility that the fuel injection amount will vary from combustion cycle to combustion cycle. Therefore, it is not desirable to frequently execute the preferably operated injector determination processing. It is desirable that the preferably operated injector determination processing is performed in a time interval of a certain length. Therefore, the preferably operated injector determination processing set forth in 3 is shown in the fuel injection system 10 of the present embodiment is carried out at predetermined time intervals.

In particular, the determining unit performs 73 of the present embodiment, the processing that 8th is shown in a predetermined calculation cycle. As in 8th shown, determines the determining unit 73 as the processing of S40 first, whether or not a predetermined time has elapsed from the previous determination time of the preferentially operated injector. Assume a case where the determining unit 73 an affirmative determination in the processing of step S40 takes place, that is, when a predetermined time has elapsed since the previous determination time of the preferably operated injector. In such a case, the determining unit performs 73 than processing step S41 the preferably operated injector determination processing set forth in 3 is shown by. The determining unit also determines 73 when processing step S41 the injector that is preferably operated and counts the time elapsed since the determination time.

When the determination unit 73 when processing step S40 makes a negative determination, that is, if a predetermined time has not elapsed from the previous determination time of the preferentially operated injector, the processing of step S41 not done. I. E. the determination unit 73 does not determine which injector is preferably operated. According to the fuel injection system 10 Further, according to the present embodiment described above, the effects and effects shown in the following, (7), can be obtained.

(7) Since the injector that is preferably operated is determined at predetermined time intervals, it is possible to avoid frequent switching of injectors. As a result, it is possible to suppress the fluctuations in the amount of fuel injection for each fuel cycle, thereby making it possible to suppress adverse effects on drivability and the like.

(First modified example)

Next, a first modified example of the fuel injection system will be discussed 10 of the sixth embodiment. As in 9 is shown in the fuel injection system 10 According to the present modification, the processing for determining whether the internal combustion engine 20th started or not when processing step S40 executed. Even with such a configuration, the injector that is preferably operated can be determined at predetermined time intervals. Therefore, the same or similar operations and effects as the operations and effects previously shown in (7) can be achieved.

(Second modified example)

Next is a second modification of the fuel injection system 10 of the sixth embodiment. As in 10 is shown in the fuel injection system 10 According to the present modification, the processing for determining whether the internal combustion engine 20th stopped or not when processing step S40 executed. Even with such a configuration, the injector that is preferably operated is determined at predetermined time intervals. Therefore, the same or similar operations and effects as the operations and effects previously shown in (7) can be achieved.

(Third modified example)

Next, a third modified example of the fuel injection system will be discussed 10 of the sixth embodiment. As in 11 is shown in the fuel injection system 10 of the present modification, the processing for determining whether or not the vehicle is stopped as the processing of step S40 executed. Even with such a configuration, the injector that is preferably operated is determined at predetermined time intervals. Therefore, the same or similar operations and effects as the operations and effects previously shown in (7) can be achieved.

(Fourth modified example)

Next will be a fourth modification of the fuel injection system 10 of the sixth embodiment. As in 12th is shown in the fuel injection system 10 According to the present modification, the processing for determining whether the fuel cut control of the internal combustion engine 20th will be executed or not as they are processing step S40 executed. Even with such a configuration, the injector that is preferably operated is determined at predetermined time intervals. Therefore, the same or similar operations and effects as the operations and effects previously shown in (7) can be achieved.

Seventh embodiment

Next will be a seventh embodiment of the fuel injection system 10 described. The following are mainly the differences to the fuel injection system 10 of the first embodiment. To change the characteristic curve of the port injection injector 40 to suppress, it is desirable to use the port injection injector 40 in a situation where the cumulative number of operations NP of the port injection injector 40 less than the maximum number of operations NPmax is to be replaced. Therefore, in the fuel injection system 10 In the present embodiment, a warning number is provided which has a value smaller than the maximum number of operations NPmax. In the previous, if the cumulative number of operations NP of the port injection injector 40 When the number of warnings is reached, a warning is triggered to replace the port injection injector 40 asked. The same applies to the direct injection injector 50 .

In particular, as indicated by the dashed line in 2 shown the control device 70 furthermore a warning device 80 having a warning to prompt for injectors to be replaced 40 and 50 can trigger. As the warning device 80 For example, a warning light provided on the dashboard of the vehicle can be used.

The control device 70 also contains a warning unit 74 that has the processing to trigger an alert to prompt the injectors to be replaced 40 and 50 via the warning device 80 performs. In particular, the warning unit performs 74 the processing carried out in 13th is shown by. Like in the 13th shown, the warning unit reads 74 than processing step S50 first the warning numbers NPth and NDth of the injectors 40 and 50 from the non-volatile memory 71 the end. The orifice injection injector's warning number NPth 40 is set to a value smaller than the maximum number of operations NPmax of the port injection injector 40 is. Further, the warning number is NDth of the direct injection injector 50 set to a value smaller than the maximum number of operations NDmax of the direct injection injector 50 is. In the present embodiment, each of the warning numbers NPth and NDth corresponds to a predetermined number of operations.

The warning unit 74 reads the cumulative number of operations NP and ND of the injectors 40 and 50 from non-volatile memory 71 than processing step S51 that on the crotch S50 follows from. The warning unit then determines 74 than processing step S52 whether or not the cumulative number of operations NP is equal to or greater than the warning number NPth, NDth. The warning unit 74 takes an affirmative determination in the processing of step S52 before when the cumulative number of operations NP of the port injection injector 40 is equal to or greater than the warning number NPth, or when the cumulative number of operations NP of the direct injection injector 50 is equal to or greater than the warning number NDth.

When the warning unit 74 a positive decision in processing step S52 undertakes, triggers the warning device 80 than processing step S53 issued a warning. In particular, when the cumulative number of operations NP of the port injection injector triggers 40 is equal to or greater than the warning number NPth, the warning unit 74 a warning about the warning device 80 to prompt the port injection injector to be replaced 40 the end. Further, when the cumulative number of operations ND of the direct injection injector triggers 50 is equal to or greater than the warning number NDth, the warning unit 74 a warning about the warning device 80 to prompt the direct injection injector to be replaced 50 the end.

According to the fuel injection system 10 Further, according to the present embodiment described above, the effects and effects shown in the following, (8), can be obtained.

(8) It is possible to replace the injectors 40 and 50 request before the cumulative number of operations NP, ND of the injectors 40 , 50 the maximum number of operations NPmax has been reached. Therefore, it is possible to avoid the use of injectors that can degrade performance. Therefore, the reliability can be ensured.

Eighth embodiment

Next will be an eighth embodiment of the fuel injection system 10 described. The following are mainly the differences to the fuel injection system 10 of the seventh embodiment. The unit of determination 73 of the present embodiment performs the processing shown in 14th is shown by. As in 14th shown, the determining unit reads 73 than processing step S60 first the maximum number of operating processes NPmax and NDmax of the injectors 40 and 50 from non-volatile memory 71 the end. The determining unit then reads 73 than processing step S61 the cumulative number of operations NP and ND of the injectors 40 and 50 from non-volatile memory 71 the end.

The unit of determination 73 determined as the processing of step S62 that on the crotch S61 follows whether the cumulative number of operations NP, ND of each injector 40 , 50 has reached the maximum number of operations NPmax, NDmax or not. When the determination unit 73 an affirmative determination in the processing of step S62 undertakes, determines the determining unit 73 than processing step S63 whether or not there is an injector whose cumulative number of operations has not reached the maximum number of operations.

When the determination unit 73 an affirmative determination in the processing of step S63 performs, operates the determining unit 73 than processing the step S64 preferably the injector whose cumulative number of operations has not reached the maximum number of operations and prevents processing of the step S63 that the injector whose cumulative number of operations has reached the maximum number of operations is operated. For example, assume a case where the cumulative number of operations NP of the port injection injector 40 is equal to or greater than the maximum number of operations NPmax and the cumulative number of operations ND of the direct injection injector 50 is less than the maximum number of operations NDmax. In such a case, the determining unit operates 73 preferably the direct injection injector 50 , taking the operation of the port injection injector 40 prevented.

On the other hand, the determination unit leads 73 than processing step S66 the preferably operated injector determination processing set forth in 2 is shown by when the determining unit 73 a negative determination in the processing of step S63 undertakes. This determines the injector that is preferably operated. According to the fuel injection system 10 According to the present embodiment described above, the effects and effects shown in the following, (9), can be obtained.

(9) Since it becomes difficult to use an injector whose cumulative number of operations has reached the maximum number of operations, the reliability can be further improved.

Ninth embodiment

Next will be a ninth embodiment of the fuel injection system 10 described. The following are mainly the differences to the fuel injection system 10 of the first embodiment.

As indicated by the dashed line in 2 shown are the injectors 40 and 50 of the present embodiment with the identification information storage units 41 and 51 intended. The identification information IDp and IDd are in the identification information storage units, respectively 41 and 51 saved. The identification information IDp is information by means of which each individual port injection injector 40 can be identified. The identification information IDd is information by means of which each individual direct injection injector 50 can be identified. An IC chip can be used as the identification information storage units, for example 41 and 51 be used. Furthermore, the identification information IDp and IDd are also in the non-volatile memory 71 saved by being through the control device 70 from the injectors 40 and 50 to be obtained.

The unit of determination 73 of the present embodiment performs the processing shown in 15th is shown by. The processing carried out in 15th is shown for each port injection injector 40 and any direct injection injector 50 carried out. However, a case in which the processing described in FIG 15th is shown for the port injection injector 40 is performed.

As shown in Fig. 15, the determining unit acquires 73 than processing step S70 the identification information IDp from the port injection injector 40 . The determining unit also reads 73 than processing step S71 the identification information IDp of the port injection injector 40 that are in the non-volatile memory 71 is saved.

Than processing step S72 determines the determining unit 73 whether the identification information IDp received from the port injection injector 40 and the identification information IDp that was obtained from the non-volatile memory 71 read out, match or not. When the identification information is different, the determination unit determines 73 that the port injection injector 40 was replaced. In this case, the determining unit sets 73 than processing step S73 the cumulative number of operations NP by setting the cumulative number of operations NP of the port injection injector 40 back to zero. The determining unit also stores 73 than processing step S74 the identification information IDp obtained at that time from the port injection injector 40 was obtained in the non-volatile memory 71 . As a result, the identification information IDp of the new port injection injector becomes 40 after replacing in the non-volatile memory 71 saved.

According to the fuel injection system 10 Further, according to the present embodiment described above, the effects and effects shown in the following, (10), can be obtained.

(10) When the injector 40 , 50 is replaced, the cumulative number of operations NP, ND is automatically reset so that the cumulative number of operations NP and ND can be counted correctly.

Other embodiments

• - Der Verbrennungsmotor 20 bei den vorherigen Ausführungsformen enthält zwei Injektoren eines Öffnungseinspritzungs-Injektors 40 und eines Direkteinspritzungs-Injektors 50. Jedoch ist die Anzahl an Injektoren, die im Verbrennungsmotor 20 vorgesehen sind, nicht auf zwei beschränkt und kann drei oder mehr sein. Ferner kann der Verbrennungsmotor 20 sowohl eine Vielzahl an Öffnungseinspritzungs-Injektoren oder eine Vielzahl von Direkteinspritzungs-Injektoren enthalten.
• - Bei dem Kraftstoffeinspritzsystem 10 bei den vorherigen Ausführungsformen können anstatt der kumulativen Anzahl an Betriebsvorgängen NP und ND der Injektoren 40 und 50 der Änderungsbetrag des Hubbetrags von jedem der Injektoren 40 und 50, der Änderungsbetrag bei der Einspritzmenge, der Änderungsbetrag im Ansprechverhalten und dergleichen verwendet werden.
• - Der Verbrennungsmotor 20, für welchen das Kraftstoffeinspritzsystem 10 bei den vorherigen Ausführungsformen verwendet wird, ist nicht auf eine Struktur beschränkt, bei welcher Injektoren 40 und 50 an jedem Zylinder 21 befestigt sind. Er kann eine Struktur aufweisen, bei welcher ein gemeinsamer Öffnungseinspritzungs-Injektor an einem stromaufwärtigen Abschnitt des Zweigabschnitts von jedem Zylinder 21 in dem Einlassdurchlass 22 vorgesehen ist.
• - Das Kraftstoffeinspritzsystem 10 bei den vorherigen Ausführungsformen wird nicht nur für einen Verbrennungsmotor 20 des Fahrzeugs, sondern auch für einen beliebigen Motor, wie etwa eine Brennstoffzelle, angewandt.
• - Die Steuerungsvorrichtung 70 und das Steuerungsverfahren davon, die in der vorliegenden Offenbarung beschrieben wurden, können mit einem oder mehreren Spezialcomputern ausgestaltet sein, welche zumindest mit einem Prozessor und zumindest einem Speicher, der programmiert ist, eine oder mehrere Funktionen, die als Computerprogramme ausgestaltet sind, durchzuführen, vorgesehen sind. Die Steuerungsvorrichtung 70 und das Steuerungsverfahren, die in der vorliegenden Offenbarung beschrieben wurden, können mit einem Spezialcomputer ausgestaltet sein, der mit zumindest einem Prozessor, der zumindest eine spezielle Hardware-Logikschaltung enthält, vorgesehen ist. Die Steuerungsvorrichtung 70 und das Steuerungsverfahren davon, die in der vorliegenden Offenbarung beschrieben wurden, können mit zumindest einem Spezialcomputer ausgestaltet sein, der als eine Kombination aus (i) einem Prozessors und einem Speicher, der programmiert ist, um eine oder mehrere Funktionen zu implementieren, und (ii) zumindest einem Prozessor, der mit zumindest eine Hardware-Logikschaltung vorgesehen ist, vorgesehen ist. Das Computerprogramm kann als Instruktionen, die durch einen Computer durchgeführt werden können, in einem greifbaren nicht flüchtigen Computer-lesbaren Medium gespeichert sein. Die spezielle Hardware-Logikschaltung und die Hardware-Logikschaltung können durch eine digitale Schaltung ausgestaltet sein, die mehrere Logikschaltungen enthält, oder sie können durch eine analoge Schaltung ausgestaltet sein.

In addition, each embodiment can also be implemented in the following embodiments.

• - The internal combustion engine 20th in the previous embodiments, one port injection injector includes two injectors 40 and a direct injection injector 50 . However, this is the number of injectors that are used in the internal combustion engine 20th are not limited to two, and may be three or more. Furthermore, the internal combustion engine 20th contain both a plurality of port injection injectors or a plurality of direct injection injectors.
• - The fuel injection system 10 in the previous embodiments, instead of the cumulative number of operations, NP and ND of the injectors 40 and 50 the amount of change in the lift amount of each of the injectors 40 and 50 , the amount of change in injection amount, the amount of change in responsiveness, and the like can be used.
• - The internal combustion engine 20th for which the fuel injection system 10 used in the previous embodiments is not limited to a structure in which injectors 40 and 50 on each cylinder 21 are attached. It may have a structure in which a common port injection injector is at an upstream portion of the branch portion of each cylinder 21 in the inlet passage 22nd is provided.
• - The fuel injection system 10 the previous embodiments are not just for an internal combustion engine 20th of the vehicle, but also for any engine such as a fuel cell.
• - The control device 70 and the control method thereof, which have been described in the present disclosure, can be configured with one or more special purpose computers, which are provided with at least one processor and at least one memory programmed to perform one or more functions that are configured as computer programs are. The control device 70 and the control method described in the present disclosure can be configured with a special purpose computer provided with at least one processor including at least one special hardware logic circuit. The control device 70 and the control method thereof described in the present disclosure can be configured with at least one special purpose computer that is configured as a combination of (i) a processor and a memory programmed to implement one or more functions, and (ii ) at least one processor, which is provided with at least one hardware logic circuit, is provided. The computer program can be stored as instructions that can be executed by a computer in a tangible non-transitory computer-readable medium. The special hardware logic circuit and the hardware logic circuit may be configured by a digital circuit including a plurality of logic circuits, or they may be configured by an analog circuit.

The present disclosure is not limited to the specific examples previously described. Specific examples previously described, which are appropriately modified in design by those skilled in the art, are also included within the scope of the present disclosure as long as the modified specific examples have the properties of the present disclosure. Each element included in each of the specific examples described above, as well as the arrangement, states, shape, and the like of the element are not limited to the illustrated ones and can be appropriately modified. The combinations of elements in each of the specific examples described above can be appropriately changed as long as there is no technical contradiction.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• JP 2019020536 [0001]
• JP 2005240581 A [0004]

Claims (19)

A fuel injection system comprising (i) a plurality of injectors including at least two injectors (40, 50), the plurality of injectors configured to inject gaseous fuel into an engine (20), (ii) a fuel tank (30) that is configured To store gaseous fuel, and (iii) a delivery line (312, 313) configured to deliver gaseous fuel from the fuel tank to each of the plurality of injectors, wherein the fuel injection system comprises: a wear amount estimating unit (72) configured to estimate a wear amount of each of the plurality of injectors; and a determination unit configured to determine which of the plurality of injectors is preferentially operated based on the amount of wear of each of the plurality of injectors estimated by the amount of wear estimating unit. Fuel injection system according to Claim 1 wherein the engine is an internal combustion engine (20). Fuel injection system according to Claim 2 wherein each cylinder (21) of the internal combustion engine is provided with at least two injectors from the plurality of injectors. Fuel injection system according to one of the Claims 1 until 3 wherein the wear amount estimating unit is further configured to estimate the wear amount of each of the plurality of injectors based on a cumulative number of operations of each of the plurality of injectors. Fuel injection system according to Claim 4 wherein the determining unit is further configured to calculate a subtraction value obtained by subtracting the cumulative number of operations from a predetermined number of operations for each of the plurality of injectors, and preferably one of the plurality of injectors that has a largest subtraction value has to operate. Fuel injection system according to Claim 4 wherein the determining unit is further configured to calculate a division value obtained by dividing the cumulative number of operations by a predetermined number of operations for each of the plurality of injectors, and preferably one of the plurality of injectors, the smallest division value has to operate. Fuel injection system according to one of the Claims 1 until 6th wherein the plurality of injectors are each provided at a plurality of corresponding positions, an identical arrangement being set for each of the plurality of cylinders in the engine; the determining unit is further configured to execute processing to determine a first injector from the plurality of injectors in a specific cylinder from the plurality of cylinders that is preferably operated, the first injector at a first corresponding position from the plurality of corresponding positions , which is set in the identical arrangement in the specific cylinder, is provided, and preferably to operate a second injector of the plurality of injectors in each of the plurality of cylinders other than the specific cylinder, the second injector on the same first corresponding position is provided in the identical arrangement in each of the plurality of cylinders other than the specific cylinder. Fuel injection system according to one of the Claims 1 until 7th wherein at least one of the plurality of injectors is a direct injection injector (50) configured to inject gaseous fuel directly into a cylinder of an engine. Fuel injection system according to Claim 8 wherein the determination unit is further configured to operate the direct injection injector regardless of the amount of wear when a load of the engine is greater than or equal to a predetermined value. Fuel injection system according to one of the Claims 1 until 6th wherein at least one of the plurality of injectors is an orifice injection injector (40) configured to inject gaseous fuel into an intake passage of the engine. Fuel injection system according to Claim 10 , further comprising: a pressure sensor (60) configured to detect a fuel pressure inside the fuel tank, the determination unit further configured to operate the port injection injector when the pressure inside the fuel tank is less or less regardless of the amount of wear is equal to a predetermined value. Fuel injection system according to one of the Claims 1 until 11 , the determining unit is further configured to execute the processing for determining which one of the plurality of injectors is preferably operated at a predetermined time interval. Fuel injection system according to one of the Claims 1 until 11 wherein the determining unit is further configured to carry out the processing of determining which one of the plurality of injectors is preferentially operated at a time when the engine is started or at a time after the engine is stopped. Fuel injection system according to one of the Claims 1 until 11 wherein the determining unit is further configured to perform the processing of determining one of the plurality of injectors that is preferentially operated at a time when a vehicle is stopped. Fuel injection system according to one of the Claims 1 until 11 wherein the determining unit is further configured to execute the processing of determining one of the plurality of injectors that is preferentially operated at a time of fuel cut control of the engine. Fuel injection system according to one of the Claims 1 until 15th further comprising: a warning unit (74) configured to issue a warning based on that the cumulative number of operations of one of the plurality of injectors corresponds to a predetermined number of operations or more. Fuel injection system according to one of the Claims 1 until 16 wherein in cases where (i) the cumulative number of operations of at least one of the plurality of injectors provided in a specific one of the plurality of cylinders of the engine has reached a predetermined number of operations, and (ii ) the cumulative number of operations of another of the plurality of injectors provided in the specific cylinder has not reached the predetermined number of operations, the determining unit is further configured to preferentially operate the other of the plurality of injectors whose cumulative Number of operations has not reached the predetermined number of operations, and to prevent at least the one of the plurality of injectors whose cumulative number of operations has reached the predetermined number of operations from being operated. Fuel injection system according to one of the Claims 1 until 17th wherein the determination unit is further configured to determine whether or not one of the plurality of injectors provided in the engine has been replaced based on identification information provided to the plurality of injectors. Fuel injection system according to Claim 18 wherein the determination unit is further configured to reset the cumulative number of operations for the one of the plurality of injectors determined to be replaced when it is determined that one of the plurality of injectors provided in the engine have been replaced.

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