JP5116096B2 - Fuel injection control device for vehicle engine - Google Patents

Description

  The present invention relates to a fuel injection control device for a vehicle engine, and more particularly to a fuel injection control device for a vehicle engine suitable for preventing a temperature increase of a three-way catalyst due to discharge of unburned gas.

Conventionally, in a vehicle equipped with an engine equipped with an electronic fuel injection device, there is a known method of limiting the vehicle speed by reducing the engine output by stopping the fuel injection or thinning out the fuel injection every predetermined number of injections. It is done. For example, in the vehicle speed limiting device for a vehicle engine described in Patent Document 1, when thinning out fuel injection or when returning from a thinning-out state to a steady injection state, the number of thinning out fuel injections is changed stepwise. I try to let them. In this way, rapid changes in engine output torque can be suppressed by performing thinning out of fuel injection and return from thinning out in stages.
JP-A 64-32047

  In general, in fuel injection, in order to improve the mixing state with air or to improve drivability, the fuel injected from the fuel injection valve is once attached to the wall surface in the intake pipe, and this attached fuel is used as the intake valve. When the valve is opened, it may be sucked into the combustion chamber together with air. In this way, the fuel adhering to the intake pipe or intake port remains slightly without flowing into the combustion chamber in one intake stroke.

  Since the intake valve is opened even when fuel injection is stopped, the fuel that has been injected and remained in the intake pipe in the cycle immediately before the stop of fuel injection burns when the valve is opened. May flow into the chamber. Since the amount of the inflowing fuel is very small, the mixing ratio with air does not become the stoichiometric air-fuel ratio, and it does not burn in the explosion stroke, generating unburned gas and raising the temperature of the three-way catalyst. Therefore, it is required to reduce the fuel remaining on the intake port in the cycle before stopping or thinning out the fuel injection.

  An object of the present invention is to provide a fuel injection control device for a vehicle engine that solves the above-described problems and meets demands and can suppress the generation of unburned gas when the vehicle speed is limited.

  In order to solve the above-mentioned problems, the present invention provides vehicle speed limit control means so that when the vehicle speed exceeds a speed limit value, fuel injection to the cylinders of the engine is stopped so that the vehicle speed does not exceed a predetermined maximum speed. In the fuel injection control device of the engine, during the vehicle speed limit control, the fuel injection timing is delayed closer to the intake valve opening period than before the vehicle speed limit control with respect to the fuel injection immediately before the stop for the cylinder where the fuel injection is stopped. The first feature is that a delay means is provided.

  The second aspect of the present invention is that the delay means implements a delay of the fuel injection timing for a plurality of fuel injections related to the cylinder including at least immediately before the stop of the fuel injection with respect to the cylinder in which the fuel injection is stopped. There are features.

  In addition, the present invention has a third feature in that a fuel cut control unit is provided that gradually increases the rate at which the fuel injection is stopped during the vehicle speed limit control toward a predetermined maximum rate.

  Furthermore, the present invention has a fourth feature in that the fuel cut control unit gradually reduces the rate at which the fuel injection is stopped when the vehicle speed is reduced to a speed limit value or less by the vehicle speed limit control. .

  According to the present invention having the first feature, the fuel injection time can overlap at least partly with the valve opening time of the intake valve. Therefore, a portion of the injected fuel that directly flows into the combustion chamber is generated, and a portion that adheres to the intake pipe wall surface can be reduced. Therefore, in the subsequent fuel injection pause cycle, the fuel flowing into the combustion chamber can be almost eliminated, so that the unburned gas can be eliminated and the temperature increase of the three-way catalyst can be suppressed.

  According to the present invention having the second feature, by reducing the amount of fuel adhering to the intake pipe wall from a plurality of cycles before the fuel injection pause cycle, the fuel flows more reliably into the combustion chamber in the fuel injection pause cycle. Can be prevented.

  According to the present invention having the third and fourth characteristics, a change in the output of the engine due to the stop of fuel injection does not occur abruptly, so that the occupant does not feel uncomfortable at the start of the vehicle speed limit and at the end of the vehicle speed limit. You can

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a system configuration diagram of a main part of a four-cycle four-cylinder gasoline engine for a motorcycle to which a fuel injection control device according to an embodiment of the present invention is applied. The engine 1 includes four cylinders 2, and an intake manifold (intake pipe) 3 and an exhaust manifold 4 are connected to each cylinder 2. Each branch pipe 3 a, 3 b, 3 c, 3 d of the intake manifold 3 is provided with a fuel injection valve (injector) 5. A throttle body 6 having a throttle valve 6a is provided in the collecting pipe 31 of the intake manifold 3, and a throttle sensor 7 for detecting a throttle opening θTH is connected to the throttle valve 6a. Further, a negative pressure sensor 8 and an intake air temperature sensor 9 are attached to the pipe wall of the collecting pipe 31. On the other hand, the oxygen concentration sensor 10 is provided in the collecting pipe 41 of the exhaust manifold 4, and the three-way catalyst 11 is provided downstream thereof. The three-way catalyst 11 purifies HC, CO, NOx, etc. in the exhaust gas.

  The engine 1 is provided with a crank angle sensor 12, a cam angle sensor 13, and an engine temperature sensor 14. The crank angle sensor 12 is provided for a crankshaft (not shown) and outputs a crank pulse at every predetermined crank angle. The cam angle sensor 13 is provided for a camshaft that opens and closes an intake valve or an exhaust valve (not shown), and is set to output a cam pulse at the compression top dead center of a specific cylinder among the four cylinders. The compression top dead center of the other cylinders is determined based on the relative crank angle between the cylinders. The engine temperature sensor 14 is provided on the water jacket wall of the engine 1 and outputs a detection signal of the cooling water temperature. Further, the fuel injection control device also includes a vehicle speed sensor 15 provided on a wheel (not shown).

  The output signals of the sensors are input to an electronic control unit (ECU) 16 having a microcomputer and used for controlling the fuel injection amount and fuel injection timing, as well as for ignition timing control.

  The ECU 16 performs vehicle speed restriction control as well as fuel injection control and ignition timing control. Vehicle speed limit control means that when the vehicle speed exceeds a preset speed limit value, fuel injection to the four cylinders is stopped at a predetermined rate, thereby reducing the engine output and limiting the vehicle speed to a predetermined maximum speed or less. Control to do.

  FIG. 3 is a diagram showing a fuel injection cycle of a plurality of cylinders. In FIG. 3, # 1 to # 4 are cylinder identification codes. As shown in the figure, when the vehicle speed is less than the speed limit value, fuel is injected into all the cylinders in the order of # 1, # 2, # 4, and # 3, and the repetition of this order is maintained. When the vehicle speed becomes equal to or higher than the speed limit value, the fuel injection performed in this cycle is stopped (fuel cut) at a predetermined rate.

  FIG. 4 is a diagram illustrating an example of a cylinder that performs fuel cut. In FIG. 4, a symbol ◯ indicates a cylinder in which fuel injection is normally performed, and a symbol x indicates a cylinder in which fuel is cut. In the example of FIG. 4A, when the vehicle speed restriction control is entered, the fuel injection of the first cylinder # 1 is cut every predetermined number of times (here, twice). In the example of FIG. 4B, the fuel injection of the first cylinder # 1 and the second cylinder # 2 is cut every predetermined number of times (here, twice).

  In this way, in the vehicle speed limit control, the engine output is limited by performing a fuel cut for a predetermined cylinder, but even if the fuel cut is performed, a small amount of fuel remaining on the intake pipe at the previous fuel injection remains. Then, in the cycle at the time of fuel cut, it flows into the combustion chamber and generates unburned gas. Therefore, in this embodiment, the next fuel injection control is performed so that fuel does not adhere to the intake pipe and remain in the cycle before the fuel cut.

  FIG. 1 is a time chart showing the fuel injection timing. FIG. 1 (a) shows the relationship between the fuel injection timing and the intake valve opening timing during normal running, that is, when the vehicle is running at a vehicle speed less than the speed limit value, and FIG. 1 (b) shows the speed limit value. When the vehicle is traveling at the above vehicle speed, that is, the relationship between the fuel injection timing and the intake valve opening timing during vehicle speed restriction control is shown.

  In FIG. 1, the fuel injection timing and the intake valve opening timing are shown in correspondence with a stage (the number in FIG. 1 indicates the stage) obtained by dividing a crank angle of 720 degrees corresponding to two revolutions of the engine, that is, four cycles, into 32 parts. Yes. In FIG. 1A, fuel injection starts at the fifth stage and ends at the eighteenth stage. The intake valve is opened from the 19th stage to the 30th stage after the fuel injection is completed. That is, the fuel injection timing and the intake valve opening timing are completely deviated from each other. This is because fuel is injected early to create a sufficient mixture state. When the intake valve is closed, that is, the fuel injected between the stages 5 to 18 adheres to the inner wall surface of the intake pipe. After that, the intake valve is opened at the stage 19 to temporarily reach the inner wall surface of the intake pipe. The sticking fuel is mixed well with the intake air and fed to the combustion chamber. However, at the timing shown in FIG. 1A, as described above, a small amount of fuel remains stuck in the intake pipe and flows into the combustion chamber at the fuel stop timing.

  Therefore, in the present embodiment, as shown in FIG. 1B, the fuel injection start timing is delayed during the vehicle speed limit control so that the fuel injection time partially overlaps the intake valve opening time. That is, fuel injection is performed between the 14th stage and the 27th stage, and the intake valve is opened between the 19th stage and the 30th stage.

  By delaying the fuel injection timing in this way, after the fuel injection is started, the fuel injected before the intake valve is opened (in stages 14 to 18) partially sticks to the inner wall of the intake pipe and then enters the combustion chamber. Most of the fuel injected after the intake valve opens (stages 19 to 27) flows directly into the combustion chamber. Accordingly, it is possible to reduce the amount of the injected fuel that adheres to the inner wall of the intake pipe. Thereby, generation | occurrence | production of unburned gas can be suppressed and the temperature rise of a three-way catalyst can be suppressed.

  The fuel injection timing is delayed in the cycle immediately before or just before the fuel cut cycle and in the cycle before that.

  Returning to FIG. 4, the timing of the vehicle speed limit control will be specifically described. In FIG. 4A, a case is assumed where the vehicle speed exceeds the speed limit value and the vehicle speed limit control is started at timing t1. In this case, at the timings t2 and t3 when the fuel injection timing of the first cylinder # 1 comes after the timing t1, the fuel injection timing is delayed and fuel injection is performed. Then, fuel cut is performed at the timing t4 when the fuel injection timing of the first cylinder # 1 comes next.

Thereafter, if the vehicle speed still exceeds the speed limit value, one cycle of the vehicle speed limit control is further executed. That is, the fuel injection is performed with the fuel injection timing delayed at the timing t5 when the fuel injection timing of the first cylinder comes next, and the second fuel cut is performed at the fuel injection timing of the first cylinder # 1 immediately thereafter. I do.
The vehicle speed limit control is started from the timing t2 when the first delayed injection is performed, and one cycle of the vehicle speed limit control is ended before the timing t5. That is, in this example, the fuel injection timing of 12 times is one cycle of the vehicle speed limit control, and the fuel is cut only once.

  Similarly in FIG. 4B, it is assumed that the vehicle speed limit control is started at the timing t1 when the vehicle speed exceeds the speed limit value. In this case, fuel injection is performed with the fuel injection timing delayed at timings t2, t3 and t4, t5 when the fuel injection timing of the first cylinder # 1 and the second cylinder # 2 comes after the timing t1. Then, fuel cut is performed at timings t6 and t7 when the fuel injection timings of the first cylinder # 1 and the second cylinder # 2 come next.

After that, if the vehicle speed still exceeds the speed limit value, further fuel injection is performed with the fuel injection timing delayed at the timing t8 when the fuel injection timing of the first cylinder and the second cylinder comes next. At the fuel injection timing of the first cylinder # 1 and the second cylinder # 2, the second fuel cut is further performed for the first cylinder # 1 and the second cylinder # 2. That is, in the example of FIG. 4B, the fuel cut is performed twice during one cycle of the vehicle speed limit control.
FIG. 5 is a block diagram showing the main functions of the ECU 16 for vehicle speed restriction control, and is common to the cylinders # 1 to # 4. In FIG. 1, the rotational speed calculation unit 17 calculates the engine rotational speed Ne based on the cycle of the crank pulse output from the crank angle sensor 12. The fuel injection amount calculation unit 18 calculates the fuel injection amount represented by the fuel injection time Ti based on the engine speed Ne and the throttle opening θTH detected by the throttle sensor 7. The calculation method may use a map showing the relationship between the fuel injection time Ti, the engine speed Ne, and the throttle opening degree θTH, or may be calculated by a predetermined calculation formula, both of which use well-known methods. be able to. The fuel injection time Ti can be corrected by the engine temperature detected by the engine temperature sensor 14, the intake air temperature detected by the intake air temperature sensor 9, or the like.

  The fuel injection timing determination unit 19 determines the fuel injection start timing based on the engine speed Ne and the throttle opening θTH. The fuel injection timing can also be corrected by parameters other than the engine speed Ne and the throttle opening θTH, such as the engine temperature.

  A crank pulse and a cam pulse are input from the crank angle sensor 12 and the cam angle sensor 13 to the fuel injection timing determination unit 19, and the crank angle of each cylinder calculated based on these input signals coincides with the fuel injection timing. When this happens, a fuel injection command is output. When a fuel injection command is input, the driver 20 causes a current to flow through the injector 5 for the fuel injection time Ti to inject fuel.

  Furthermore, this embodiment includes a maximum speed limit control function for preventing the vehicle speed from exceeding a predetermined maximum speed. For the maximum speed limit control, a fuel cut control unit 21 for stopping the fuel injection command output from the fuel injection timing determination unit 19, a delay means 22 for delaying the fuel injection timing, and a fuel cut and fuel injection timing delay target A cylinder determination unit 23 for detecting the cylinder is provided.

  The vehicle speed determination unit 23 and the fuel cut control unit 21 and the delay unit 22 are used when the vehicle speed of the motorcycle detected by the vehicle speed sensor 15 exceeds a predetermined speed limit value so that the vehicle speed does not exceed a predetermined maximum speed. And input the vehicle speed detection signal. The cylinder discrimination unit 24 performs cylinder discrimination based on the cam pulse and the crank pulse. The fuel cut control unit 21 determines a predetermined fuel cut target cylinder based on the cylinder identification signal from the cylinder determination unit 23 and outputs a fuel cut command. The delay means 22 determines a cylinder whose fuel injection timing is to be delayed based on the cylinder identification signal, and outputs a delay command.

  The fuel injection command is paused by the fuel cut command and is not input to the driver 20. The fuel injection command is delayed by the delay command and input to the driver 20.

  Next, the operation of the vehicle speed limiting control shown in FIG. 4A will be described with reference to the flowcharts of FIGS. In FIG. 6, in step S <b> 1, the vehicle speed V is calculated from the output signal of the vehicle speed sensor 15. In step S2, it is determined whether or not the vehicle speed V is equal to or higher than a scheduled speed limit value VLMT. If step S2 is affirmative, the process proceeds to step S3 to set a control flag indicating that the vehicle speed limit control is being performed. And it progresses to step S4 and performs vehicle speed restriction | limiting control.

  If step S2 is negative, the process proceeds to step S5 to determine whether or not the vehicle speed limit control is being performed. Whether or not the vehicle speed limit control is being performed is determined by the in-control flag. If the vehicle speed limit control is being performed, the process proceeds to step S6 to cancel the vehicle speed limit control. In canceling the vehicle speed limit control, the fuel cut and the delay control of the fuel injection timing before the fuel cut are finished, and the fuel is normally injected into the cylinder for each cylinder identification. If the vehicle speed limit control is canceled in step S6, the process is exited because the vehicle is in a normal traveling state that is not a high-speed traveling near the maximum speed.

  FIG. 7 is a flowchart showing details of the vehicle speed limit control. In step S401 in FIG. 7, it is determined whether or not the first cylinder # 1 has been identified based on the cylinder identification signal based on the cam pulse from the cam angle sensor 13. In step S402, the counter value C1 of the cylinder counter is set to “1”. The cylinder counter indicates the number of the four cylinders in the fuel injection cycle, and is a circulation counter that is reset to “1” when the counter value C1 becomes “4”. The counter value C1 “1” indicates the first cylinder, that is, the first cylinder # 1 in the injection order of FIG. 3 according to the injection order of the fuel injection cycle shown in FIG. Similarly, the counter value C1 “2” indicates the second cylinder # 2, the counter value C1 “3” indicates the fourth cylinder # 4, and the counter value C1 “4” indicates the third cylinder # 3.

  In step S403, the counter value C2 of the delayed injection counter is initialized to “0”. The delay injection counter is a counter that counts the number of fuel injections (delayed injections) with a delayed fuel injection timing. This delayed injection counter is reset to “0” when the counter value C2 becomes “2”.

  In step S404, it is determined whether or not the counter value C1 is “1” indicating the first cylinder # 1. Initially, the counter value C1 is initialized in step S402 to "1", so step S404 is affirmative. If step S404 is positive, the process proceeds to step S405, and it is determined whether or not the counter value C2 is “2”. If the delayed injection is performed twice, step S405 is affirmative and the routine proceeds to step S406, where fuel cut is performed for the cylinder. That is, fuel injection is not performed. Until the delayed injection is performed twice, step S405 is negative and the process proceeds to step S407 to perform the delayed injection shown in FIG. In step S408, the counter value C2 is incremented (+1) in accordance with the delayed injection in step S407.

  After the fuel is cut in step S406 or after the delayed injection, after the counter value C2 is incremented in step S408, the process proceeds to step S410 and the counter value C1 is incremented. If it is determined in step S404 that the counter value C1 is not “1”, the process proceeds to step S409, fuel injection is normally performed, and the process proceeds to step S410.

  In step S411, it is determined whether or not the counter value C1 is “4”. That is, it is determined whether or not the fuel injection control for one cycle of four cylinders has been completed. If step S411 is negative, the process proceeds to step S404. If step S411 is positive, the process returns to the main routine (FIG. 6) to determine the vehicle speed.

  When the operation of FIG. 7 is associated with FIG. 4A, at the timings t2 and t3 of FIG. 4A, step S404 is affirmative and step S405 is negative, so delayed injection of step S407 is performed. Since the counter value C2 becomes “2” after the two delayed injections, the fuel cut is performed at the timing t4. For the fuel injection in the cylinders other than the timings t2, t3, t4, and t5 in FIG. 4 (a), that is, the cylinders other than the first cylinder, the determination in step S404 is negative. Therefore, normal fuel injection is performed without delay. The

  The vehicle speed limiting control of FIG. 4B can also be implemented by modifying the process shown in the flowchart of FIG. In the vehicle speed limiting control of FIG. 4B, the value at which the counter value C2 of FIG. 6 is reset can be modified.

  FIG. 8 is a flowchart corresponding to the vehicle speed restriction control of FIG. In FIG. 8, the same processing as in FIG. In FIG. 8, in step S501, it is determined whether or not the first cylinder # 1 has been identified. In step 502, the counter value C1 of the cylinder counter is set to “1”.

  In step S503, the counter value C2 of the delayed injection counter is initialized to “0”. In this example, the delay injection counter is reset to “0” when the counter value C2 becomes “4”. This is because when four delayed injections are performed as shown in FIG. 4B, fuel cut is performed at timings t6 and t7.

  In step S504, it is determined whether or not the counter value C1 is “1” indicating the first cylinder # 1. Initially, the counter value C1 is initialized in step S502 to be “1”, so step S504 is affirmative. If step S504 is positive, the process proceeds to step S505, and it is determined whether or not the counter value C2 is “4”. When step S505 is affirmative, the delayed injection for the two cylinders is performed twice, for a total of four times, so the process proceeds to step S506, and the fuel is cut for the cylinder.

  When the delayed injection has not been performed four times, the result of step S505 is negative, so the process proceeds to step S507 to perform the delayed injection shown in FIG. In step S508, the counter value C2 is incremented according to the delayed injection in step S407.

  After the fuel cut in step S506 or after delayed injection, after the counter value C2 is incremented in step S508, the process proceeds to step S510 and the counter value C1 is incremented. If it is determined in step S504 that the counter value C1 is not “1”, the process proceeds to step S509, and it is determined whether or not the counter value C1 is “2” indicating the second cylinder # 2. If step S509 is negative, it is neither the first cylinder # 1 nor the second cylinder # 2, so the process proceeds to step S510, fuel injection is normally performed, and the process proceeds to step S511.

In step S512, it is determined whether or not the fuel injection control for one cycle is completed by determining whether or not the counter value C1 is “4”. If step S512 is negative, the process proceeds to step S504. If step S512 is positive, the process returns to the main routine (FIG. 6) to determine the vehicle speed.
In the above example, the fuel injection timing is delayed at the time of two fuel injections for each of the cylinders to be cut before the fuel is cut. However, immediately before the fuel cut, that is, at timing t3 in FIG. The fuel injection timing may be delayed only at the timings t4 and t5 of (b).

  In the above example, the fuel cut ratio is 1/12 or 2/12, but the present invention is not limited to this. For example, in one cycle of the vehicle speed limit control in FIG. 4B, the number of cylinders that perform fuel cut is further increased, and fuel cut is also performed for cylinder # 4 or # 3 immediately after timings t6 and t7, so that the fuel cut ratio is 3 / 12 or 4/12.

  Furthermore, in the vehicle speed limit control, the fuel cut ratio may be gradually increased instead of limiting the vehicle speed at a fixed fuel cut ratio. This is because if the fuel cut ratio is small, the vehicle speed may not be reduced quickly, but if the fuel cut ratio is set to be large in advance, the vehicle speed may be drastically reduced and the passenger may feel uncomfortable.

  FIG. 9 is a diagram illustrating an example in which the fuel cut ratio is increased step by step. FIG. 9A shows a case where all 10 fuel injections are normally performed. FIG. 9B shows a case where the fuel cut is performed only once in 10 fuel injection operations. FIG. 9C shows a case where the fuel cut is performed twice in 10 fuel injection operations. FIG. 9D shows a case where the fuel cut is performed three times in the fuel injection operation ten times.

  The fuel cut ratio switching shown in FIG. 9 may be continued until the switching from the ratio of FIG. 9 (a) to FIG. 9 (d) is completed, and when the vehicle speed becomes lower than the speed limit value, FIG. It is also possible to end the process without switching to the ratio (d), that is, the final target ratio.

  In any of these cases, the fuel injection of the cylinder at least once immediately before is controlled so as to delay the injection timing and reduce the amount of fuel sticking to the wall surface of the intake pipe. In FIG. 9, the black circles are marked on the cylinders whose fuel injection timing has been delayed.

  Even when the vehicle speed returns to the speed limit value or less during the vehicle speed limit control, it is preferable not to finish the fuel cut at a time, but to control the ratio of the cylinders that gradually cut the fuel. That is, the control shown in (d) of FIG. 9 is shifted to the control shown in (a).

  Further, in the above-described embodiment, the fuel injection timing is determined based on the engine speed Ne and the throttle opening θTH according to two cases, that is, when the vehicle speed limit control is not being performed and when the vehicle speed limit control is not being performed. The fuel injection timing can be determined when the stroke is determined by stroke determination and the opening timing of the intake valve is clear. However, in recent years, the cam pulser has been abolished in order to reduce the number of parts, and the stroke is sometimes determined based on the intake negative pressure and the crank pulse. As described above, in an engine that does not use a cam pulser, there is a case in which the stroke determination cannot be performed and the valve opening timing of the intake valve is unknown. Therefore, in an engine not equipped with such a cam pulser, when the stroke becomes unknown during the vehicle speed limit control, another preset fuel different from the above two cases is required until the stroke is determined. Use injection timing. For example, fuel is injected at a preset stage among stages formed by dividing a crank angle of 720 degrees by a predetermined angle.

  The above-described embodiment is an embodiment of the present invention, and the present invention is not limited to this. For example, the fuel cut ratio can be arbitrarily changed, and the method of discriminating the cylinder that cuts the fuel or the cylinder that delays the fuel injection timing is not limited to the processing shown in FIGS. In short, when the vehicle speed exceeds the planned speed limit value, the fuel injection timing for the cylinder that will be fuel-cut at least in the previous cycle including the immediately preceding cycle is closer to the intake valve opening period than in the normal time. It is only necessary to perform shifting control.

It is a figure which shows the relationship between the fuel-injection timing of the fuel-injection control apparatus which concerns on one Embodiment of this invention, and the valve opening timing of an intake valve. 1 is a system configuration diagram of an engine to which a fuel injection control device of the present invention is applied. It is a figure which shows the fuel-injection cycle of multiple cylinders. It is a figure which shows the example of the cylinder which carries out a fuel cut. It is a block diagram which shows the principal part function of ECU for vehicle speed restriction | limiting control. It is a flowchart which shows operation | movement of vehicle speed limitation control. It is a flowchart which shows the detailed operation | movement (the 1) of vehicle speed limitation control. It is a flowchart which shows the detailed operation | movement (the 2) of vehicle speed limitation control. It is a figure which shows the example which increases a fuel cut ratio in steps.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Cylinder, 3 ... Intake manifold (intake pipe), 4 ... Exhaust manifold, 5 ... Fuel injection valve (injector), 7 ... Throttle sensor, 12 ... Crank angle sensor, 13 ... Cam angle sensor, 15 ... Vehicle speed sensor, 16 ... ECU

Claims (3)

In the engine fuel injection control device provided with the vehicle speed limit control means so that the vehicle speed does not exceed a predetermined maximum speed by stopping the fuel injection to the cylinder of the engine when the vehicle speed exceeds the speed limit value,
While the vehicle speed is limited, the fuel injection timing immediately before the stop for the cylinder where the fuel injection is stopped is provided with delay means for delaying the fuel injection timing closer to the intake valve opening period than before the vehicle speed limit,
The delay means includes a configuration that opens the intake valve during fuel injection and delays the fuel injection start timing so that the fuel injection ends while the intake valve is open , and the fuel injection is stopped. cylinder regard, multiple fuel injection relating to the gas cylinder is configured to implement a delay of the fuel injection timing fuel injection control apparatus for an engine according to claim Rukoto including last pause least fuel injection. During vehicle speed limiting control, fuel injection control device for an engine according to claim 1, wherein that you have provided the fuel cut control section which stepwise increases toward the rate at which halting the fuel injection to the maximum percentage of scheduled . The fuel cut control section, when the vehicle speed by the vehicle speed limit control falls below the speed limit, the fuel of the engine according to claim 1, wherein that you reduce the rate of halting the fuel injection stages Injection control device.

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