JP4075644B2 - Internal combustion engine output control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an internal combustion engine output control apparatus that executes an output increase correction process by start assist correction for a vehicle drive internal combustion engine when the vehicle starts.
[0002]
[Prior art]
In a vehicle equipped with an internal combustion engine as a drive source, an output increase amount is obtained from the accelerator opening and the rotation speed of the internal combustion engine in order to assist the vehicle start, and the start assist correction is performed on the output of the internal combustion engine based on the output increase amount. An internal combustion engine control device has been proposed (see, for example, Patent Document 1). This device increases the output in response to a sudden increase in load on the internal combustion engine at the time of starting to prevent engine stall, thereby enabling smooth starting.
[0003]
[Patent Document 1]
Japanese Unexamined Patent Publication No. 2001-73842 (page 5-6, FIG. 2-5)
[0004]
[Problems to be solved by the invention]
However, in the above prior art, a completely different required torque value is used in the internal combustion engine operation region at the time of starting and other than that. In particular, the start assist correction is set independently regardless of whether the internal combustion engine is operating or not.
[0005]
For this reason, especially when the internal combustion engine operating region is switched at the time of starting or immediately after starting, the calculation of the required torque value is newly started without reflecting the friction of the internal combustion engine in the immediately preceding operating region. The internal combustion engine speed and / or vehicle speed may decrease or increase, causing the driver to feel uncomfortable.
[0006]
An object of the present invention is to prevent the driver from feeling uncomfortable when the internal combustion engine operating region is switched at the time of starting or immediately after starting in the internal combustion engine output control device that executes the start assist correction in this way. It is.
[0007]
[Means for Solving the Problems]
In the following, means for achieving the above object and its effects are described.
An internal combustion engine output control device according to claim 1 is an internal combustion engine output control device that executes an output increase correction process by a start assist correction at the time of start of a vehicle with respect to an internal combustion engine for driving a vehicle. A region-attached output correction amount to be calculated is provided for each internal combustion engine operation region, and the start assist correction is performed based on the total amount of the region-attached output correction amount. The present invention is characterized by comprising output correction means for switching the gain at the time of calculating the output correction amount corresponding to each operation region of the internal combustion engine.
[0008]
The output correction means does not calculate and use the output correction amount separately for each internal combustion engine operation region, but the calculation target is a separate region-attached output correction amount for each internal combustion engine operation region, but the start assist correction itself Is performed based on the total amount of all region-attached output correction amounts.
[0009]
For this reason, even if the internal combustion engine operating region is switched at the time of starting or immediately after starting, the output correction amounts attached to the respective regions are totaled and are always reflected in the starting assist correction in relation to each other.
[0010]
Moreover, since the output correction means switches the gain when calculating the region-attached output correction amount corresponding to each internal combustion engine operation region, the operation state of the internal combustion engine is an appropriate response for each internal combustion engine operation region. This is reflected in the output correction amount attached to the area. Thus, even if the internal combustion engine operating region is switched, the start assist correction can be executed immediately with an appropriate response to the new internal combustion engine operating region.
[0011]
This prevents fluctuations in the internal combustion engine speed and the vehicle speed when the internal combustion engine operating region is switched at the time of starting or immediately after starting, so that the driver does not feel uncomfortable.
[0012]
In the internal combustion engine output control apparatus according to claim 2, in claim 1, the gain is one or both of a gain when the region-attached output correction amount is obtained by a calculation formula and a gain when the gain is obtained from a map. It is characterized by being.
[0013]
As described above, the gain may be either a calculation formula, a map or a gain, or may be a gain when a combination of both is used.
In the internal combustion engine output control device according to claim 3, in claim 1 or 2, the output correction means includes a first region that is during idling stop, a second region that is during start, In addition, the second region is divided into third regions that are other than these and compared with each gain when calculating the region-attached output correction amount of the first region and the region-attached output correction amount of the third region. A large gain is set when calculating the region-attached output correction amount.
[0014]
The internal combustion engine operation region can be divided into the above-mentioned three regions and provided with region-attached output correction amounts for individual calculation. In this case, the output correction means compares the region-attached output correction amount of the first region and the region-attached output correction amount of the third region with each gain when calculating the region-attached output correction amount of the third region. Set a large gain when calculating the quantity. In the second region at the time of starting, a sudden increase in load occurs with respect to the internal combustion engine. Therefore, the internal combustion engine is operated by setting the gain when calculating the region-related output correction amount in the second region to be larger than the others. When the region is switched at the time of starting, the region-attached output correction amount in the second region can be increased with high response in response to an increase in load. As a result, the total amount of all region-attached output correction amounts also changes with high response, and appropriate start assist correction can be executed based on this total amount.
[0015]
Further, when the internal combustion engine operation region changes from the second region to another region, the gain for calculating the region-attached output correction amount becomes small, so that problems such as output hunting are less likely to occur.
[0016]
This prevents fluctuations in the internal combustion engine speed and the vehicle speed when the internal combustion engine operating region is switched at the time of starting or immediately after starting, so that the driver does not feel uncomfortable.
[0017]
The internal combustion engine output control apparatus according to claim 4, wherein the output correction means is a first region where the internal combustion engine operating region is stopped by engaging the clutch, and the clutch is released. Are divided into a second region and a third region where the vehicle is engaged with the clutch engaged, and the region attached output correction amount of the first region and the region attached output correction amount of the third region are respectively set. The gain for calculating the region-attached output correction amount of the second region is set to be larger than each gain for calculation.
[0018]
More specifically, the internal combustion engine operation region is divided into three regions. More specifically, the first region where the clutch is engaged and stopped, the second region where the clutch is released, and the clutch is engaged. The vehicle is divided into third areas where the vehicle is traveling.
[0019]
As a result, the gain at the time of calculating the region attached output correction amount in the second region where the clutch is disengaged is set to be larger than that in the two regions where the clutch is engaged, so that the start time is included. In response to an increase in load when switching to two regions, the region-attached output correction amount in the second region can be increased with high response. As a result, the total amount of all region-attached output correction amounts also changes with high response, and appropriate start assist correction can be executed based on this total amount.
[0020]
Further, when the region changes from the second region to another region, the gain for calculating the region-attached output correction amount becomes small, so that problems such as output hunting are less likely to occur.
[0021]
This prevents fluctuations in the internal combustion engine speed and the vehicle speed when the internal combustion engine operating region is switched at the time of starting or immediately after starting, so that the driver does not feel uncomfortable.
[0022]
The internal combustion engine output control apparatus according to claim 5, wherein the region-attached output correction of the third region is compared with the gain in calculating the region-attached output correction amount of the first region in claim 3 or 4. It is characterized in that the gain for calculating the quantity is set small.
[0023]
Further, in the first region and the third region, the gain when calculating the region-attached output correction amount of the third region may be set small. The third region is during normal traveling, and it is difficult to slow down the internal combustion engine rotation. When the acceleration operation is not performed, it is necessary to travel stably. Therefore, it is preferable to make the gain particularly small.
[0024]
As a result, fluctuations in the internal combustion engine speed and vehicle speed can be prevented, and the effect of preventing the driver from feeling uncomfortable is enhanced.
The internal combustion engine output control apparatus according to claim 6, wherein the output correction means is a first region in which the internal combustion engine operating region is stopped by engaging the clutch, and the clutch is released. The second region where the vehicle is stopped, the third region where the clutch is traveling and the fourth region where the clutch is engaged, and the region attached output correction amount of the first region. , When calculating the region-attached output correction amount of the second region, compared to each gain when calculating the region-attached output correction amount of the third region and the region-attached output correction amount of the fourth region, respectively. The gain is set large.
[0025]
In the internal combustion engine operating region, the first region where the clutch is engaged and stopped, the second region where the clutch is released and stopped, the third region where the clutch is released and traveling and the clutch are engaged And you may divide into the 4th field which is running.
[0026]
In this case, the gain for calculating the region-related output correction amount in the second region where the clutch is released and stopped is set to be larger than the other three regions, so that the second region where the start is performed is set. In response to an increase in load when switching, the region-attached output correction amount in the second region can be increased with high response. As a result, the total amount of all region-attached output correction amounts also changes with high response, and appropriate start assist correction can be executed based on this total amount.
[0027]
Further, when the region changes from the second region to another region, the gain for calculating the region-attached output correction amount becomes small, so that problems such as output hunting are less likely to occur.
[0028]
This prevents fluctuations in the internal combustion engine speed and the vehicle speed when the internal combustion engine operating region is switched at the time of starting or immediately after starting, so that the driver does not feel uncomfortable.
[0029]
The internal combustion engine output control apparatus according to claim 7, wherein the region-attached output correction amount of the first region, the region-attached output correction amount of the third region, and the region-attached output correction amount of the fourth region are defined in claim 6. Or when calculating each region-attached output correction amount in the order of the region-attached output correction amount of the third region, the region-attached output correction amount of the first region, and the region-attached output correction amount of the fourth region. The gain is set small.
[0030]
Furthermore, for the remaining three regions, the gains may be set smaller in the order of the first region, the third region, and the fourth region, or in the order of the third region, the first region, and the fourth region. Since one or both of the first region and the third region include the state immediately after the start and there is a possibility that the load on the internal combustion engine at the time of start still remains, even within the three regions It belongs to the larger one. Since the fourth region is running with the clutch engaged, the gain is made smaller than those in the first region and the third region to prevent sudden acceleration. As a result, it is possible to execute a more appropriate start assist correction by calculating the output correction amount associated with each region with appropriate responsiveness.
[0031]
The internal combustion engine output control apparatus according to claim 8, wherein the output correction is not required as start assist in an operation state where no acceleration request is required or in an internal combustion engine operation region where start assist correction is not executed. Output correction amount attenuation means for attenuating the amount is provided.
[0032]
When a large value is set for the region-attached output correction amount, if the start assist correction is performed again, the internal combustion engine speed may increase rapidly. Therefore, in this way, it is possible to prevent the driver from feeling uncomfortable if the output correction amount that has become unnecessary as starting assistance is attenuated in advance. However, if the output correction amount is decreased when there is an acceleration request, there is a risk that the acceleration performance during acceleration operation may become uncomfortable. Further, in the internal combustion engine operating region where the start assist correction is being performed, if the output correction amount is decreased, the internal combustion engine rotation may become unstable.
[0033]
For this reason, the output correction amount attenuating means attenuates the output correction amount that is no longer necessary as start assist in a driving state where no acceleration request is required or in an internal combustion engine operation region where start assist correction is not performed, thereby making the driver more uncomfortable. It can be effectively prevented.
[0034]
The internal combustion engine output control apparatus according to claim 9, wherein the internal combustion engine is a diesel engine, and the output increase correction process is an increase correction of a fuel injection amount. To do.
[0035]
Note that when the internal combustion engine is a diesel engine, the output increase correction process by the start assist correction is an increase correction of the fuel injection amount, so that the start assist correction can be appropriately executed as the fuel increase process.
[0036]
DETAILED DESCRIPTION OF THE INVENTION
[Embodiment 1]
FIG. 1 is a schematic configuration diagram showing an accumulator diesel engine (common rail diesel engine) 2 as a first embodiment, and a fuel injection system and a control system thereof. The accumulator diesel engine 2 is mounted on a vehicle as an automobile engine.
[0037]
The diesel engine 2 is provided with a plurality of cylinders (four cylinders in the present embodiment, but only one cylinder is illustrated) # 1, # 2, # 3, and # 4, and each cylinder # 1. The injectors 4 are provided for the combustion chambers # 4 to # 4, respectively. Fuel injection from the injector 4 to each cylinder # 1 to # 4 of the diesel engine 2 is controlled by turning on and off the electromagnetic valve 4a for injection control.
[0038]
The injector 4 is connected to a common rail 6 as an accumulator pipe common to each cylinder. While the electromagnetic valve 4a for injection control is open, fuel in the common rail 6 is sent from the injector 4 to each cylinder # 1 to # 4. Is injected into the inside. A relatively high pressure corresponding to the fuel injection pressure is accumulated in the common rail 6. In order to realize this pressure accumulation, the common rail 6 is connected to the discharge port 10 a of the supply pump 10 via the supply pipe 8. A check valve 8 a is provided in the middle of the supply pipe 8. Due to the presence of the check valve 8a, the supply of fuel from the supply pump 10 to the common rail 6 is allowed, and the reverse flow of fuel from the common rail 6 to the supply pump 10 is prevented.
[0039]
The supply pump 10 is connected to the fuel tank 12 through a suction port 10b, and a filter 14 is provided in the middle thereof. The supply pump 10 sucks fuel from the fuel tank 12 through the filter 14. At the same time, the supply pump 10 reciprocates the plunger by a cam synchronized with the rotation of the diesel engine 2 to increase the fuel pressure to a required pressure and supplies the high-pressure fuel to the common rail 6.
[0040]
Further, a pressure control valve 10 c is provided in the vicinity of the discharge port 10 a of the supply pump 10. This pressure control valve 10c is for controlling the fuel pressure discharged toward the common rail 6 from the discharge port 10a. By opening the pressure control valve 10c, surplus fuel not discharged from the discharge port 10a is returned from the return port 10d provided in the supply pump 10 to the fuel tank 12 via the return pipe 16. Yes.
[0041]
An intake passage 18 and an exhaust passage 20 are connected to the combustion chambers of the cylinders # 1 to # 4 of the diesel engine 2, respectively. A throttle valve is provided in the intake passage 18, and the flow rate of the intake air introduced into the combustion chamber is adjusted by adjusting the opening of the throttle valve according to the operating state of the diesel engine 2.
[0042]
A glow plug 22 is disposed in the combustion chamber of each cylinder # 1 to # 4 of the diesel engine 2. The glow plug 22 becomes red hot when a current is passed through the glow relay 22a immediately before the diesel engine 2 is started, and a part of the sprayed fuel is blown onto the glow plug 22 to promote ignition and combustion. Device.
[0043]
The diesel engine 2 is provided with the following various sensors, switches, and the like, and detects the operating state of the diesel engine 2. That is, as shown in FIG. 1, an accelerator opening sensor 26 for detecting the accelerator opening ACCP is provided for the accelerator pedal 24. The diesel engine 2 is provided with a starter 30 for starting the diesel engine 2. The starter 30 is provided with a starter state detection switch 30a for detecting its operating state. The cylinder block of the diesel engine 2 is provided with a water temperature sensor 32 for detecting the temperature of the cooling water (cooling water temperature THW). The return pipe 16 is provided with a fuel temperature sensor 36 for detecting the fuel temperature THF. The common rail 6 is provided with a fuel pressure sensor 38 for detecting the pressure of fuel in the common rail 6.
[0044]
The crankshaft of the diesel engine 2 is provided with an engine rotation sensor 40 for detecting the crank angle and the engine speed based on the rotation of the crankshaft. Further, the rotation of the crankshaft is transmitted to each camshaft for opening and closing the intake valve 18a and the exhaust valve 20a via a timing belt or the like. These camshafts are set to rotate at a rotation speed ratio of 1/2 that of the crankshaft. Among them, the intake camshaft for opening and closing the intake valve 18a is configured as a cylinder discrimination sensor 42 by providing a pulsar having one tooth and a pickup near the pulsar. In the first embodiment, the engine speed NE and the crank angle CA are calculated from the pulse signals output from both the sensors 40 and 42. Further, a clutch switch 44 for detecting whether or not the clutch pedal is depressed is provided, and a vehicle speed sensor 46 for detecting the vehicle speed SPD from the rotational speed of the output shaft is provided on the output shaft side of the transmission.
[0045]
In the first embodiment, an electronic control unit (ECU) 52 for executing various controls of the diesel engine 2 is provided. The ECU 52 controls the diesel engine 2 such as fuel injection amount control and glow energization control. Each process for controlling is performed. The ECU 52 includes a CPU, a ROM that stores various programs and maps, a RAM that temporarily stores calculation results of the CPU, a backup RAM that stores calculation results and prestored data, a timer counter, an input interface, an output interface, and the like It is comprised centering on the microcomputer provided with. The ECU 52 receives signals from the accelerator opening sensor 26, the starter state detection switch 30a, the water temperature sensor 32, the fuel temperature sensor 36, the fuel pressure sensor 38, the engine rotation sensor 40, the cylinder discrimination sensor 42, the clutch switch 44, the vehicle speed sensor 46, and the like. Reading. Further, the electromagnetic valve 4a, the pressure control valve 10c, the glow relay 22a, etc. are connected to the ECU 52 via drive circuits, respectively. Thus, the ECU 52 performs control calculation based on the signal data read as described above, and drives and controls the electromagnetic valve 4a, the pressure control valve 10c, the glow relay 22a, and the like.
[0046]
Next, the fuel injection amount control process executed by the ECU 52 will be described. This process is as shown in the flowcharts of FIGS. 2, 3, 4 and 5, and is a process that is interrupted and executed every 180 ° CA rotation since the diesel engine 2 has four cylinders in this case.
[0047]
When this processing is started, first, as described above, the accelerator opening ACCP, the engine speed NE, the clutch switch state CLSW, the vehicle speed SPD, and the like obtained based on the signals from the sensors and switches are stored in the RAM of the ECU 52. (S102).
[0048]
Next, based on the governor pattern as shown in FIG. 6, the low rotation side fuel injection amount Qbase1 and the medium and high rotation side fuel injection amount Qbase2 are calculated (S104). These fuel injection amounts Qbase1 and Qbase2 are calculated by a calculation formula using the engine speed NE and the accelerator opening ACCP as parameters.
[0049]
As shown in the figure, the low-rotation-side fuel injection amount Qbase1 for each accelerator opening ACCP slopes downward with respect to the engine speed NE, and the coefficient of the calculation formula is set so that this angle is steep. For this reason, the value of the low rotation side fuel injection amount Qbase1 rapidly increases as the engine speed NE becomes lower. On the other hand, the medium and high rotation side fuel injection amount Qbase2 is inclined downward to the right with respect to the engine speed NE. It is. For this reason, the value of the medium-high rotation side fuel injection amount Qbase2 increases more gradually than the low rotation side fuel injection amount Qbase1 as the engine speed NE becomes lower. As will be described later, the actual fuel injection amount is the larger of “Qbase1 + QiscON + QiscOFF” and “Qbase2”. As a result, “Qbase1 + QiscON + QiscOFF” is used on the low rotation side, and “Qbase2” is used on the medium / high rotation side.
[0050]
Once these fuel injection amounts Qbase1 and Qbase2 are calculated, the target rotational speed NEisc is set (S106). The target rotational speed NEisc is set based on the friction of the diesel engine 2, the vehicle running resistance, the electric load, etc., or the prediction of their occurrence.
[0051]
For example, when the clutch connecting the diesel engine 2 and the transmission side is released (including a half clutch) (CLSW = “ON”) and stopped (vehicle speed SPD ≦ SPDstop), the clutch is Thus, NEisc = “850 rpm” is set in anticipation of the vehicle being started. When the clutch is engaged (CLSW = “OFF”) and the vehicle is traveling (vehicle speed SPD> SPDstop), NEisc = “850 rpm” is set in consideration of traveling resistance. When the clutch is engaged (CLSW = “OFF”) and the vehicle is stopped (vehicle speed SPD ≦ SPDstop), NEisc = “800 rpm” is set. In addition, as the stop determination value SPDstop, values of “0 km / h” to “3 km / h” are set. Here, the stoppage determination value SPDstop = “0 km / h” is set. However, “0 km / h” includes a traveling state of less than “3 km / h” because of the accuracy of the vehicle speed sensor 46.
[0052]
Next, the three fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2 are calculated and updated according to the situation (S108). The calculation process of these fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2 is shown in the flowchart of FIG.
[0053]
In this process, it is first determined whether or not the clutch switch state CLSW = “OFF (engaged)” (S202). If CLSW = “OFF (engaged)” (“YES” in S202), it is determined whether or not the vehicle is next traveling, that is, whether or not the vehicle speed SPD> SPDstop (S204). Here, the detected value of the vehicle speed sensor 46 is SPDstop = 0 km / h.
[0054]
If the vehicle is stopped or slightly running, that is, if SPD = SPDstop (“NO” in S204), the process of calculating the second fuel injection correction amount QiscOFF2 at the time of clutch off is executed (S206). In the calculation process of the second fuel injection correction amount QiscOFF2 at the time of clutch off, first, the proportional correction amount Qa2 is obtained from the map a2 of FIG. 7 based on ΔNE (= NEisc−NE). Note that Qa2 = “0” is fixed when ΔNE <“0”. That is, the proportional correction amount Qa2 is set according to the degree of decrease in the engine speed NE with respect to the target speed NEisc.
[0055]
Further, an integral value Sqb2 is obtained from the map b2 in FIG. 7 based on ΔNE. Then, the second fuel injection correction amount QiscOFF2 at the time of clutch off is calculated as in the following equation 1.
[0056]
[Expression 1]
QiscOFF2 ← Qa2 + ΣSqb2 [Equation 1]
Here, the integral correction amount ΣSqb2 is a value obtained by integrating the integral value Sqb2 for each calculation of Equation 1 (ΣSqb2 ← ΣSqb2 + Sqb2).
[0057]
Thus, the process of calculating the fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2 is exited (S108). Therefore, if the second fuel injection correction amount QiscOFF2 at the time of clutch off is calculated in step S206, the calculation processing is not performed for the other two fuel injection correction amounts QiscON and QiscOFF1. Therefore, the two fuel injection correction amounts QiscON and QiscOFF1 are not updated, and the values calculated before this are maintained.
[0058]
When it is determined that SPD> SPDstop (“YES” in S204), a calculation process of the clutch-off first fuel injection correction amount QiscOFF1 is executed (S208). In the calculation process of the first fuel injection correction amount QiscOFF1 when the clutch is off, first, the proportional correction amount Qa1 is obtained from the map a1 of FIG. 8 based on ΔNE (= NEisc−NE). Note that Qa1 = “0” when ΔNE <“0”. That is, the proportional correction amount Qa1 is set according to the degree of decrease in the engine speed NE with respect to the target speed NEisc.
[0059]
Further, an integral value Sqb1 is obtained from the map b1 in FIG. 8 based on ΔNE.
The gains of the proportional correction amount Qa1 and the integral value Sqb1 with respect to ΔNE in the maps a1 and b1 in FIG. 8 are set lower than the gains of the proportional correction amount Qa2 and the integral value Sqb2 with respect to ΔNE in the maps a2 and b2 in FIG. is there.
[0060]
Then, the first fuel injection correction amount QiscOFF1 at the time of clutch off is calculated as in the following equation 2.
[0061]
[Expression 2]
QiscOFF1 ← Qa1 + ΣSqb1 [Formula 2]
Here, the integral correction amount ΣSqb1 is a value obtained by integrating the integral value Sqb1 for each calculation of Equation 2 (ΣSqb1 ← ΣSqb1 + Sqb1).
[0062]
Thus, the process of calculating the fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2 is exited (S108). Therefore, if the first fuel injection correction amount QiscOFF1 at the time of clutch off is calculated in step S208, the calculation process is not performed for the other two fuel injection correction amounts QiscON and QiscOFF2. Therefore, the two fuel injection correction amounts QiscON and QiscOFF2 are not updated, and the values calculated before this are maintained.
[0063]
If it is determined in step S202 that CLSW = “ON (disengaged)” (“NO” in S202), then a process for calculating the clutch-on-time fuel injection correction amount QiscON is executed (S210). In the process of calculating the clutch-on-time fuel injection correction amount QscON, first, the proportional correction amount Qas is obtained from the map as in FIG. 9 based on ΔNE (= NEisc−NE). Note that Qas = “0” is fixed when ΔNE <“0”. That is, the proportional correction amount Qas is set according to the degree of decrease in the engine speed NE with respect to the target speed NEisc.
[0064]
Further, an integral value Sqbs is obtained from the map bs in FIG. 9 based on ΔNE.
Further, the differential correction amount Qcs is obtained from the map cs of FIG. 9 according to the time change ΔNE / dt of ΔNE. Note that Qcs = “0” when ΔNE / dt <“0”. That is, the differential correction amount Qcs is set according to the degree of decrease in the engine speed NE with respect to the target speed NEisc.
[0065]
The gains of the proportional correction amount Qas and the integral value Sqbs with respect to ΔNE in the maps as and bs in FIG. 9 are set larger than the gains of the proportional correction amount Qa2 and the integral value Sqb2 with respect to ΔNE in the maps a2 and b2 in FIG. is there. As a result, the degree of decrease in the engine speed NE with respect to the target speed NEisc is largely reflected in the proportional correction amount Qas and the integral value Sqbs.
[0066]
Then, as shown in the following equation 3, the clutch-on-time fuel injection correction amount QiscON is calculated.
[0067]
[Equation 3]
QiscON ← Qas + ΣSqbs + Qcs ... [Formula 3]
Here, the integral correction amount ΣSqbs is a value obtained by integrating the integral value Sqbs for each calculation of Equation 3 (ΣSqbs ← ΣSqbs + Sqbs). As described above, in contrast to the calculations for the other two fuel injection correction amounts QiscOFF1 and QiscOFF2, in the calculation of the clutch-on time fuel injection correction amount QiscON, ΔNE is greatly reflected in the proportional correction amount Qas and the integral value Sqbs. is there. Therefore, the change in ΔNE is greatly reflected in the clutch-on-time fuel injection correction amount QiscON.
[0068]
Thus, the process of calculating the fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2 is exited (S108). Therefore, if the clutch-on-time fuel injection correction amount QiscON is calculated in step S210, the other two fuel injection correction amounts QiscOFF1 and QiscOFF2 are not calculated. Therefore, the two fuel injection correction amounts QiscOFF1 and QiscOFF2 are not updated, and the values calculated before this are maintained.
[0069]
Thus, any one of the fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2 is calculated and updated in step S108. That is, the second fuel injection correction amount QiscOFF2 is updated when the clutch is off when the clutch is engaged and the vehicle stops or is extremely slow. If the clutch is engaged and the vehicle is traveling at a certain speed or more, the first fuel injection correction amount QiscOFF1 is updated when the clutch is off. When the clutch is disengaged, the clutch-on-time fuel injection correction amount QiscON is updated.
[0070]
Each fuel injection correction amount QiscON, QiscOFF1, QiscOFF2 and each integral correction amount ΣSqb1, ΣSqb2, ΣSqbs are set to “0” at the initial setting when the ignition is turned on.
[0071]
When the calculation process (S108) of the fuel injection correction amounts QiscON, QiscOFF1, QiscOFF2 is completed in this way, a start assist correction amount attenuation process is executed (S110). This start assist correction amount attenuation process is shown in the flowcharts of FIGS. When this process is started, it is first determined whether or not CLSW = “OFF (engaged)” (S302). For example, it is assumed that the vehicle is stopped in a state where the transmission is neutral and the clutch is engaged in order to wait for an intersection signal. In this case, since CLSW = “OFF (engaged)” (“YES” in S302), it is next determined whether ACCP = 0 (%), that is, whether the driver has not depressed the accelerator pedal 24 or not. Is determined (S304). If ACCP = 0 (“YES” in S304), it is determined whether the engine speed NE is currently equal to or higher than the target speed NEisc set in the state of CLSW = “OFF” (S306). If NE ≧ NEisc (“YES” in S306), then whether or not the clutch-injection fuel injection correction amount QiscOFF> “0” (mm 3), that is, the amount of increase by the clutch-off fuel injection correction amount QiscOFF It is determined whether correction has been made (S308).
[0072]
Here, if the clutch-injection fuel injection correction amount QiscOFF = “0” (“NO” in S308), then whether or not the clutch-on-time fuel injection correction amount QiscON> “0” (mm 3), that is, the clutch on. It is determined whether or not the increase correction by the hour fuel injection correction amount QiscON has been made (S312). Even when NE <NEisc (“NO” in S306), the determination in step S312 is executed.
[0073]
Here, when the clutch-on-time fuel injection correction amount QiscON = “0” (“NO” in S312), the process exits the start assist correction amount attenuation process and returns to FIG. QiscOFF is calculated from the two fuel injection correction amounts QiscOFF1 and QiscOFF2 (S112).
[0074]
[Expression 4]
QiscOFF ← QiscOFF1 + QiscOFF2 [Formula 4]
Next, the final fuel injection amount Qfin is calculated as shown in the following equation 5 using the clutch-off time fuel injection correction amount QiscOFF and the clutch-on time fuel injection correction amount QiscON (S114).
[0075]
[Equation 5]
Qfin ←
MAX (Qbase1 + QiscON + QiscOFF, Qbase2) ... [Formula 5]
Here, MAX () is an operator that extracts the larger numerical value in (). Note that “Qbase1 + QiscON + QiscOFF” is as shown by a one-dot chain line in FIG.
[0076]
In this way, this process is once completed. In such an idle state such as waiting for a signal (CLSW = “OFF (engaged)”, ACCP = “0”, SPD = “0”), fuel injection when the engine speed NE is lower than the target speed NEisc The amount adjustment is made by calculating the second fuel injection correction amount QiscOFF2 when the clutch is off (FIG. 3: S206). Since the second fuel injection correction amount QiscOFF2 at the time of clutch off is set with a smaller gain than ΔNE as compared with the fuel injection correction amount QiscON at the time of clutch on as described above, hunting for idle speed control occurs. Hateful. However, since it is set with a gain larger than the first fuel injection correction amount QiscOFF1 when the clutch is off, it is possible to cope with a decrease in the engine speed NE when the vehicle is stopped in an idle state with higher responsiveness than when traveling, and to engine stall Can deal effectively.
[0077]
From the state described above, it is assumed that CLSW = “ON (released)” is obtained by first depressing the clutch pedal in order to start the vehicle idle (“NO” in S302). In this case, ACCP = 0 (“YES” in S318), and if the starting load is not applied to the diesel engine 2 and NE ≧ NEisc (“NO” in S320), “NO” in step S312 Is determined. Accordingly, calculation of the clutch-off fuel injection correction amount QiscOFF according to Equation 4 (S112) and calculation of the final fuel injection amount Qfin according to Equation 5 (S114) are executed. Further, the calculation process of the clutch-on-time fuel injection correction amount QiscON is performed (FIG. 3: S210). However, since the engine speed NE is not lower than NEisc, the value does not actually increase.
[0078]
Thereafter, with the CLSW = “ON (open)”, the transmission is set to the first speed and becomes a half-clutch, and the load at the start is applied to the diesel engine 2. Therefore, NE <NEisc (“YES” in S320). For this reason, the calculation of the clutch-off fuel injection correction amount QiscOFF according to Equation 4 (S112) and the final fuel injection amount Qfin according to Equation 5 (S114) are immediately executed.
[0079]
In such a start state where CLSW = “ON (open)”, the fuel injection amount adjustment for converging the engine speed NE to the target speed NEisc is performed by performing step S210 (FIG. 3). It is adjusted by the value of the injection correction amount QiscON. As described above, the clutch-on-time fuel injection correction amount QiscON is set with a larger gain than ΔNE as compared to the clutch-off first fuel injection correction amount QiscOFF1 and the clutch-off second fuel injection correction amount QiscOFF2. Yes. Moreover, since the differential correction amount Qcs is also added, the value increases rapidly, and a sufficient output can be generated from the diesel engine 2 against the load at the time of start. Even if the gain for calculating the clutch-on fuel injection correction amount QiscON is large, the clutch-on-time fuel injection correction amount QiscON opposes the load at the time of starting, so that hunting in output control is unlikely to occur.
[0080]
When the clutch is completely engaged by the driver's clutch pedal operation after the half-clutch state has passed, CLSW changes to “OFF (engaged)” (“YES” in S302). Then, it is determined whether or not ACCP = “0”, that is, whether or not the driver is executing an acceleration operation (S304).
[0081]
Here, since it is an idle start (ACCP = “0”) where the driver is not accelerating (“YES” in S304), the process proceeds to the determination in step S306. If NE ≧ NEisc (“YES” in S306) and QiscOFF = “0” (“NO” in S308), or NE <NEisc (“NO” in S306), then whether or not QiscON> “0”. Is determined (S312). Here, at the time of the immediately preceding start, the clutch-on-time fuel injection correction amount QiscON rapidly increases. Therefore, since QiscoON> “0” (“YES” in S312), the clutch-on-time fuel injection correction amount QiscoON is attenuated (S314).
[0082]
This clutch-on-time fuel injection correction amount QiscoON attenuation process is a process of gradually decreasing the QiscON> 0 state to a value of QiscON = “0”. Specifically, for each control cycle of the fuel injection amount control process, a process of subtracting a certain amount from the clutch-on-time fuel injection correction amount QiscoON until QiscoON = 0 is executed. Alternatively, a process of subtracting a certain amount from the clutch-on-time fuel injection correction amount QiscON may be executed until QiscON = 0 in the time period. Further, instead of subtracting a certain amount from the fuel injection correction amount QiscoON at the time of clutch on, the damping coefficient (<1) is multiplied by the fuel injection correction amount QiscON at the time of clutch on to obtain the fuel injection correction amount QiscoON at the time of clutch on. If it approaches to “0” to some extent, the attenuation process may be terminated with QscON = 0.
[0083]
Then, the above-described calculation of the clutch-off fuel injection correction amount QiscOFF according to the equation 4 (S112) and the final fuel injection amount Qfin according to the equation 5 (S114) are executed, and this processing is temporarily terminated. Thereafter, if ACCP = 0 continues (“YES” in S304), while QiscoON> 0 (“YES” in S312), the clutch on-time fuel injection correction amount QscON attenuation processing (S314) continues. To do.
[0084]
When the clutch-on-time fuel injection correction amount QiscON is attenuated after the start, the second fuel at the time of clutch-off is “YES” in step S202 in FIG. 3 and while SPD = 0 (“NO” in S204). The injection correction amount QiscOFF2 is updated (S206). If SPD> 0 (“YES” in S204), the first fuel injection correction amount QiscOFF1 when the clutch is off is updated (S208). Therefore, if NE <NEisc, the clutch-injection fuel injection correction amount QiscOFF increases in place of the clutch-on-time fuel injection correction amount QiscON, thereby preventing engine stall.
[0085]
On the other hand, consider a case where the driver depresses the clutch pedal to set CLSW = “ON” (“NO” in S302) and depresses the accelerator pedal 24 for starting. In this case (“NO” in S318), it is then determined whether the value of “Qbase1 + QiscON + QiscOFF1 + QiscOFF2” is greater than Qbase2 (S322). That is, when the current fuel injection amount Qbase1, Qbase2 and the fuel injection correction amount QiscON, QiscOFF1, QiscOFF2 are used, it is determined whether or not “Qbase1 + QiscON + QiscOFF” is extracted in step S114.
[0086]
If “Qbase1 + QiscON + QiscOFF1 + QiscOFF2> Qbase2” (“YES” in S322), “Qbase1 + QiscON + QiscOFF” should be used as the final fuel injection amount Qfin. In this case, the above-described calculation of the clutch-off fuel injection correction amount QiscOFF according to Equation 4 (S112) and the calculation of the final fuel injection amount Qfin according to Equation 5 (S114) are executed, and this processing is temporarily terminated. As a result, a value of “Qbase1 + QiscON + QiscOFF” is used as the final fuel injection amount Qfin.
[0087]
At this time, since CLSW = “ON” (FIG. 3: “NO” in S202), the clutch-on-time fuel injection correction amount QiscON increases due to a large gain, particularly during half-clutch (S210).
[0088]
If the clutch is completely engaged and CLSW = “OFF” (“YES” in S302), then ACCP> “0” (“NO” in S304), so whether “Qbase1 + QiscON + QiscOFF1 + QiscOFF2> Qbase2” or not. Is determined (S316). This determination is the same processing as step S322 (FIG. 5) described above. Here, if “Qbase1 + QiscON + QiscOFF1 + QscOFF2> Qbase2” (“YES” in S316), the calculation of Expression 4 (S112) and the calculation of Expression 5 (S114) described above are executed, and this process is temporarily terminated. As a result, a value of “Qbase1 + QiscON + QiscOFF” is used as the final fuel injection amount Qfin.
[0089]
At this time, although CLSW = “OFF” (FIG. 3: “YES” in S202), it is still a slight speed, and if the vehicle speed SPD = 0 is detected by the vehicle speed sensor 46 (“NO” in S204), A second fuel injection correction amount QiscOFF2 at the time of clutch off is calculated (S206). However, since the clutch-on fuel injection correction amount QiscON is sufficiently large, the clutch-off second fuel injection correction amount QiscOFF2 does not actually increase. Thereafter, if the vehicle speed SPD> 0 (“YES” in S204), the clutch-off first fuel injection correction amount QiscOFF1 having the smallest gain is calculated (S208). However, in this case as well, since the clutch-on-time fuel injection correction amount QiscON is sufficiently large, the clutch-off-time first fuel injection correction amount QiscOFF1 does not actually increase.
[0090]
When the driver depresses the accelerator pedal 24, the engine speed NE increases thereafter, and “Qbase1 + QiscON + QiscOFF1 + QiscOFF2 ≦ Qbase2” (“NO” in S316). At this time, since the engine speed NE is higher than the target speed NEisc (“YES” in S306), if QiscOFF> “0” (S308), the clutch-off fuel injection correction amount QiscOFF is attenuated. (S310). This attenuation process is the same as the above-described attenuation process (S314) of the clutch-on-time fuel injection correction amount QiscON.
[0091]
Since QiscON> “0” (“YES” in S312), the clutch-on-time fuel injection correction amount QiscON is attenuated (S314). Then, the above-described calculation of Expression 4 (S112) and calculation of Expression 5 (S114) are executed, and this process is temporarily terminated.
[0092]
Thereafter, if the clutch-injection fuel injection correction amount QiscOFF = “0” (“NO” in S308), the clutch-off fuel injection correction amount QiscOFF attenuation processing (S310) stops. Similarly, if the clutch-on-time fuel injection correction amount QiscON = “0” (“NO” in S312), the clutch-on-time fuel injection correction amount QiscON attenuation process (S314) stops.
[0093]
If ACCP> “0” is changed to ACCP = “0” (“YES” in S304), NE ≧ NEisc (“YES” in S306) and QscOFF> “0” (“YES” in S308). ") As long as the clutch-off time fuel injection correction amount QiscOFF is attenuated (S310). As long as QiscON> 0 (“YES” in S312), the clutch-on-time fuel injection correction amount QiscON attenuation process (S314) is continued.
[0094]
An example of processing by the above-described fuel injection amount control processing (FIGS. 2 to 5) is shown in the timing charts of FIGS. FIG. 10 shows the case of idle start. FIG. 11 shows a case where the driver starts with the accelerator pedal 24 depressed.
[0095]
In the case of FIG. 10, until the time t1, the transmission is neutral, and the vehicle is stopped waiting for a signal with the clutch engaged. Accordingly, until the time t1, the calculation of the second fuel injection correction amount QiscOFF2 when the clutch is off (S206) is executed, and the calculation processing of the other fuel injection correction amounts QiscON and QiscOFF1 is stopped. In order to depart, the clutch is released at time t1, and the transmission is gear-changed to the first speed. From this time t1, the calculation of the clutch-on fuel injection correction amount QiscON having a large gain (S210) is executed, and the calculation processing of the other fuel injection correction amounts QiscOFF1 and QiscOFF2 is stopped. Therefore, the clutch-on-time fuel injection correction amount QiscON is increased as the target rotational speed NEisc increases, and the actual engine rotational speed NE converges to the target rotational speed NEisc with high response.
[0096]
Then, by starting the clutch engagement operation from time t2, the rotational load on the diesel engine 2 increases from time t2, and the engine speed NE tends to drop from the target speed NEisc. However, when the clutch-on-time fuel injection correction amount QiscON increases with a high response, the start assist correction amount (QiscON + QiscOFF) increases rapidly, and the engine speed NE recovers and approaches the target speed NEisc. Such an increase in the start assist correction amount prevents engine stall at the time of start, and enables a smooth start.
[0097]
Thereafter, the vehicle starts traveling, and at time t3, the clutch is completely engaged and CLSW = “OFF”. At this time, the vehicle speed SPD detected from the vehicle speed sensor 46 is still “0”. Accordingly, the calculation of the clutch-on-time fuel injection correction amount QiscON (FIG. 3: S210) is stopped, and the process proceeds to the calculation of the clutch-off-time second fuel injection correction amount QiscOFF2 (S206). Further, since the accelerator pedal 24 is not depressed at time t3 (ACCP = “0”), the clutch-on-time fuel injection correction amount QiscON is immediately started to be attenuated (FIG. 4: S314). Thereafter, since SPD> 0 at time t4, the calculation of the second fuel injection correction amount QiscOFF2 when the clutch is off (S206) is stopped and the calculation of the first fuel injection correction amount QiscOFF1 when the clutch is off (S208). Be started.
[0098]
Since QiscON = “0” at time 5 (“NO” in FIG. 4: S312), the clutch-on-time fuel injection correction amount QiscON is not attenuated (S314).
[0099]
At time t6, accelerator pedal 24 is depressed (“NO” in S304), engine speed NE further increases, and accordingly vehicle speed SPD also increases. However, as long as it is determined that the engine speed is low ("YES" in S316), the clutch-off fuel injection correction amount QiscOFF is not attenuated (S310) (t6 to t7). After that, when the engine speed NE is increased to reach a mid-high speed range (“NO” in S316), NE ≧ NEisc (“YES” in S306) and QiscOFF> “0” (“YES” in S308). The off-time fuel injection correction amount QiscOFF is attenuated (S310) (t7 to t8).
[0100]
In the case of FIG. 11, the transition until the time t2 in FIG. 10 is the same until the clutch engagement is started (time t12). In the case of FIG. 11, the accelerator pedal 24 is depressed before CLSW = “OFF” (time 13). For this reason, even when CLSW = “OFF” (FIG. 4: “YES” in S302) at time t14, ACCP> “0” (“NO” in S304), and still in the low speed range (“YES” in S316). )), The clutch-on-time fuel injection correction amount QiscON is not attenuated (S314). Therefore, the value of the clutch-on fuel injection correction amount QiscON is maintained, and at the same time, the clutch-off fuel injection correction amount QiscOFF is also maintained.
[0101]
Thereafter, when the engine is in the mid-high rotation range ("NO" in S316) or when the accelerator pedal 24 is completely returned ("YES" in S304), the clutch-on fuel injection correction amount QscON and the clutch-off fuel Attenuation with the injection correction amount QiscOFF is executed (t15 to t16). Therefore, as shown by the broken line, higher acceleration can be obtained as compared with the case where the damping of the clutch-on fuel injection correction amount QiscON is started immediately after starting.
[0102]
The above-described configuration corresponds to the case where the internal combustion engine operation region is divided into three. That is, the driving region where CLSW = “OFF” and SPD = “0” corresponds to the first region when idling, and the driving region where CLSW = “ON” corresponds to the second region when starting, The driving region where CLSW = “OFF” and SPD> “0” corresponds to the third region which is a region other than these. The first fuel injection correction amount QiscOFF1 when the clutch is off, the second fuel injection correction amount QiscOFF2 when the clutch is off, and the fuel injection correction amount QiscON when the clutch is on correspond to the region-attached output correction amount. “QiscON + QiscOFF” corresponds to the total amount of the region-attached output correction amount. Of the fuel injection amount control processing (FIGS. 2 to 5), steps S108, S112, and S114 correspond to processing as output correction means, and step S110 corresponds to processing as output correction amount attenuation means.
[0103]
According to the first embodiment described above, the following effects can be obtained.
(I). Each of the fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2 is updated by being separately calculated for each operation region of the internal combustion engine, but the start assist correction itself is performed for all the fuel injection correction amounts QisON, The total amount is QiscOFF1 and QiscOFF2.
[0104]
Therefore, even if the internal combustion engine operating region is switched at the time of starting or immediately after starting, the respective fuel injection correction amounts QscON, QiscOFF1, and QiscOFF2 are totalized and are always reflected in the start assist correction.
[0105]
In addition, the gain when each of the fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2 is calculated is switched to a magnitude corresponding to each internal combustion engine operating region. From this, the operating state of the diesel engine 2 is reflected in the fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2 with appropriate responsiveness for each operation region of the internal combustion engine. Therefore, even if the internal combustion engine operation region is switched, the start assist correction can be immediately executed with appropriate response to the new internal combustion engine operation region.
[0106]
As a result, it is possible to prevent fluctuations in the engine speed NE and the vehicle speed SPD when the internal combustion engine operating region is switched at the time of starting or immediately after starting, so that the driver does not feel uncomfortable.
[0107]
(B). The gain at the time of calculating the clutch-on-time fuel injection correction amount QscON is maximized. At the time of starting, a sudden load increase occurs with respect to the diesel engine 2. Therefore, by setting the gain to be larger than the other fuel injection correction amounts QiscOFF1, QiscOFF2, the clutch-on-time fuel injection correction amount QiscON can be made highly responsive to an increase in load when starting. Can be raised. As a result, the total amount of the fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2 also changes with high response, and appropriate start assist correction can be executed based on this total amount.
[0108]
Further, when the vehicle is changed from the start time to another region, the gain when calculating the fuel injection correction amount QiscOFF1, QiscOFF2 at the time of clutch off becomes small, so that problems such as output hunting do not occur and the engine speed is reduced. NE and vehicle speed SPD are stabilized.
[0109]
As a result, it is possible to prevent fluctuations in the engine speed NE and the vehicle speed SPD when the internal combustion engine operation region is switched at the time of starting or immediately after starting, so that the driver does not feel uncomfortable.
[0110]
(C). Furthermore, in the operation region where CLSW = “OFF” and SPD> “0”, and the operation region where CLSW = “OFF” and SPD = “0”, CLSW = “OFF” and SPD> “0”. The gain in the operation area is reduced. This region is during normal travel, and the engine speed NE is unlikely to drop, and it is necessary to travel stably when acceleration operation is not performed. For this reason, by making the gain smaller than the driving region where CLSW = “OFF” and SPD = “0”, fluctuations in the engine speed NE and the vehicle speed SPD can be prevented, and an effect of preventing the driver from feeling uncomfortable. Rise.
[0111]
(D). If a large value is set for the fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2, the engine speed NE may increase rapidly if the start assist correction is performed again. Therefore, in this way, the fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2, which are no longer necessary as starting assistance, can prevent the driver from feeling uncomfortable when attenuated in advance. However, if the fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2 are decreased when there is an acceleration request, there is a possibility that the acceleration performance during the acceleration operation may become uncomfortable. Further, in the internal combustion engine operating region where the start assist correction is being performed, if the fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2 are decreased, the engine speed NE and the vehicle speed SPD may become unstable.
[0112]
For this reason, it is not necessary as start assistance in a state where there is no acceleration request (“YES” in S304, “YES” in S318) or in an internal combustion engine operating region where “NO” is executed (“NO” in S316, “NO” in S322). Thus, it is possible to attenuate the fuel injection correction amounts QiscON and QiscOFF. This effectively prevents the driver from feeling uncomfortable.
[0113]
[Embodiment 2]
In the present embodiment, the processes of FIGS. 12 to 15 are executed instead of the fuel injection amount control process (FIGS. 2 to 5) of the first embodiment. 12 to 15 are different from the processes of FIGS. 2 to 5 in that the driving region in the clutch-on state is divided into two at vehicle speed SPD> “0” and SPD = “0”. Thus, the clutch-on-time fuel injection correction amount is calculated when CLSW = “ON” and SPD> “0”, and the clutch-on-time first fuel injection correction amount QiscON1, CLSW = “ON”, and SPD = “ The second fuel injection correction amount QiscON2 is calculated when the clutch is on.
[0114]
In FIG. 12, steps S402 to S406, S412, and S414 are the same as steps S102 to S106, S112, and S114 of FIG. 2, and steps S408, S410, and S411 are different.
[0115]
The calculation process (S408) of the fuel injection correction amounts QiscON1, QiscON2, QiscOFF1, and QiscOFF2 will be described. The details of this process are as shown in the flowchart of FIG. Here, steps S502 to S508 are the same as steps S202 to S208 in FIG. In FIG. 13, when CLSW = “ON” (“NO” in S502), if the vehicle is running (“YES” in S510), the first fuel injection correction amount QiscON1 at the time of clutch on is calculated (S514). If the vehicle is stopped (“NO” in S510), the second fuel injection correction amount QiscON2 at the time of clutch on is calculated (S512).
[0116]
The start assist correction amount attenuation process (S410) will be described. The details of this process are as shown in the flowcharts of FIGS. Here, steps S602 to S614, S618, and S620 are the same processes as steps S302 to S314, S318, and S320 of FIGS. 14 and 15, in steps S616 and S622, it is determined whether or not the engine is in the low rotation region by determining “Qbase1 + QiscON1 + QiscON1 + QiscOFF1 + QiscOFF2> Qbase2”.
[0117]
In step S411 in FIG. 12, the clutch-on-time fuel injection correction amount QiscON is calculated from the two fuel injection correction amounts QiscON1 and QiscON2 by the following equation (6).
[0118]
[Formula 6]
QiscON <-QiscON1 + QiscON2 [Formula 6]
The first fuel injection correction amount QiscOFF1 when the clutch is off is calculated using the same map as the map shown in FIG. 8 of the first embodiment, and the second fuel injection correction amount QiscOFF2 when the clutch is off is the same as that of the first embodiment. It is calculated with the same map as the map shown in FIG. The map for calculating the clutch-on-time first fuel injection correction amount QiscON1 is calculated using the same map as the map shown in FIG. 9 of the first embodiment. The map for calculating the second fuel injection correction amount QiscON2 at the time of clutch-on uses the three maps shown in FIG. 9, but the map corresponding to the maps as and bs has a gain larger than that in FIG. Is set to
[0119]
That is, the second fuel injection correction amount QiscON2 when the clutch is on is the largest gain for ΔNE, the first fuel injection correction amount QiscON1 when the clutch is on, the second fuel injection correction amount QiscOFF2 when the clutch is off, and the first fuel injection when the clutch is off The correction amount is set to decrease in the order of QiscOFF1.
[0120]
An example of processing by the above-described fuel injection amount control processing (FIGS. 12 to 15) is shown in the timing charts of FIGS. FIG. 16 shows the case of idle start. FIG. 17 shows a case where the driver starts with the accelerator pedal 24 depressed.
[0121]
In the case of FIG. 16, until time t31, CLSW = “OFF” (FIG. 13: “YES” in S502) and SPD = “0” (“NO” in S504). Calculation of the fuel injection correction amount QiscOFF2 (S506) is executed. Calculation processing of the other fuel injection correction amounts QiscON1, QiscON2, and QiscOFF1 is stopped. Then, the clutch is released at time t31 for shifting. From this time t31, the calculation of the second fuel injection correction amount QiscON2 at the time of clutch-on with the maximum gain is executed, and the calculation processing of the other fuel injection correction amounts QiscON1, QiscOFF1, QiscOFF2 is stopped.
[0122]
Then, from time t32, by starting the clutch engagement operation for idling start, the load on the diesel engine 2 increases rapidly, and the engine speed NE drops from the target speed NEisc. However, since the second fuel injection correction amount QiscON2 at the time of clutch-on increases with a high response, the start assist correction amount (QiscON + QiscOFF) is rapidly increased, and the engine speed NE is brought close to the target speed NEisc. Such a rapid increase in the start assist correction amount (QiscON + QiscOFF) prevents engine stall and enables smooth start.
[0123]
Thereafter, when SPD> SPDstop is detected by the vehicle speed sensor 46 at time t33 (FIG. 13: “YES” in S510), the first fuel injection at clutch-on is substituted for the second fuel injection correction amount QiscON2 at clutch-on. The correction amount QiscON1 is calculated. The calculation of the first fuel injection correction amount QiscON1 when the clutch is on is also a relatively high response gain, but the gain is smaller than the second fuel injection correction amount QiscON2 when the clutch is on. For this reason, the increase in the start assist correction amount is moderated to some extent.
[0124]
Then, when the clutch is completely engaged at time t34 and CLSW = “OFF”, the calculation of the first fuel injection correction amount QiscON1 when the clutch is on is stopped, and the calculation of the first fuel injection correction amount QiscOFF1 when the clutch is off ( The process proceeds to FIG. 13: S508). Since the accelerator pedal 24 is not depressed at time t34 (ACCP = “0”), the clutch-on-time fuel injection correction amount QiscON is immediately started to be attenuated (FIG. 14: S614). Thereafter, QiscON = “0” at time t36, but a drop in the engine speed NE is prevented by increasing the first fuel injection correction amount QiscOFF1 at the time of clutch-off at time t35.
[0125]
Then, at time t37, the accelerator pedal 24 is depressed, and the engine speed NE further increases, and the vehicle speed SPD also increases accordingly. After that, when the medium / high speed rotation range is reached (“NO” in S616: t38), since NE ≧ NEisc (“YES” in S606) at this time, as long as QiscOFF> “0” (“YES” in S608). Is executed to attenuate the fuel injection correction amount QiscOFF at the time of clutch off (S610) (t38 to t39).
[0126]
In the case of FIG. 17, the transition to the time t32 in FIG. 16 is the same until the clutch engagement is started (time t42). In the case of FIG. 17, the accelerator pedal 24 is depressed before CLSW = “OFF” (time t43). Therefore, even if CLSW = “OFF” (FIG. 14: “YES” in S602) at time t45, ACCP> “0” (“NO” in S604). Since the engine speed is still in the low rotation range (“YES” in S616), the attenuation (S614) of the clutch-on-time fuel injection correction amount QiscoON is not started. Therefore, the value of the clutch-on fuel injection correction amount QiscON is maintained, and at the same time, the clutch-off fuel injection correction amount QiscOFF is also maintained.
[0127]
Thereafter, when the engine is in the mid-high rotation range ("NO" in S616) or when the accelerator pedal 24 is completely returned ("YES" in S604), the clutch-on fuel injection correction amount QiscON and the clutch-off fuel Attenuation with the injection correction amount QiscOFF is executed (t47 to t48). Therefore, as shown by the broken line, the acceleration performance is better as compared with the case where the damping of QiscON is started immediately after the clutch is engaged.
[0128]
The above-described configuration corresponds to the case where the internal combustion engine operation region is divided into four. That is, the operation region where CLSW = “OFF” and SPD = “0” corresponds to the first region, the operation region where CLSW = “ON” and SPD = “0” corresponds to the second region, and CLSW = “ The operating region where “ON” and SPD> “0” corresponds to the third region, and the operating region where CLSW = “OFF” and SPD> “0” corresponds to the fourth region.
[0129]
The first fuel injection correction amount QiscOFF1 when the clutch is off, the second fuel injection correction amount QiscOFF2 when the clutch is off, the first fuel injection correction amount QiscON1 when the clutch is on, and the second fuel injection correction amount QiscON2 when the clutch is on It corresponds to. “QiscON + QiscOFF” corresponds to the total amount of the region-attached output correction amount.
[0130]
Steps S408, S411, S412, and S414 in the fuel injection amount control processing (FIGS. 12 to 15) correspond to processing as output correction means. Step S410 corresponds to processing as output correction amount attenuation means.
[0131]
According to the second embodiment described above, the following effects can be obtained.
(I). The effects (a) to (d) of the first embodiment are produced.
(B). In the initial stage of starting, the engine output is rapidly increased so as to cope with a rapid load increase at the start of traveling of the vehicle with the maximum gain by the second fuel injection correction amount QiscON2 at the time of clutch on. Thereafter, the gain is reduced to mitigate the rapid increase in engine output, so that the vehicle speed after starting can be prevented from being accelerated more than necessary, so that the driver does not feel uncomfortable after starting.
[0132]
[Other embodiments]
(A). The fuel injection correction amounts QiscOFF1, QiscOFF2, and QiscON of the first embodiment and the fuel injection correction amounts QiscOFF1, QiscOFF2, QiscON1, and QiscON2 of the second embodiment are obtained on a map. Instead of this, it may be obtained by a calculation formula constituted by a gain having a magnitude corresponding to the operating range of the internal combustion engine. Alternatively, the fuel injection correction amount may be calculated using both the map and the calculation formula.
[0133]
(B). In each of the embodiments described above, the clutch has been described as being operated by the driver. However, the present invention can be similarly applied to a case where the automatic clutch is automatically released and engaged when starting or shifting. .
[0134]
(C). In each said embodiment, although the diesel engine was demonstrated as an internal combustion engine, it is applicable also to a gasoline engine. In the case of a gasoline engine, in the case of uniform combustion at the stoichiometric air-fuel ratio, the cylinder output gasoline engine in which the engine output is adjusted by adjusting the opening of the electronic throttle valve and stratified combustion is performed In this case, the engine output is adjusted by the fuel injection amount as in the case of the diesel engine.
[0135]
(D). In each of the above-described embodiments, a fuel injection amount increasing process for acceleration assist may be added in addition to start assist.
(E). In the second embodiment, the magnitude of the calculation gain is gradually reduced in the order of QiscON2, QiscON1, QiscOFF2, and QiscOFF1, but may be gradually reduced in the order of QiscON2, QiscOFF2, QiscON1, and QiscOFF1, for example, depending on the engine. .
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing a pressure accumulating diesel engine, a fuel injection system, and a control system according to a first embodiment.
FIG. 2 is a flowchart of a fuel injection amount control process executed by the ECU according to the first embodiment.
FIG. 3 is a flowchart of processing for calculating fuel injection correction amounts QiscON, QiscOFF1, and QiscOFF2.
FIG. 4 is a flowchart of a start assist correction amount attenuation process.
FIG. 5 is a flowchart of a start assist correction amount attenuation process.
FIG. 6 is an explanatory diagram of a governor pattern used in the fuel injection amount control process.
FIG. 7 is an explanatory diagram of a map for obtaining a second fuel injection correction amount QiscOFF2 when the clutch is off.
FIG. 8 is an explanatory diagram of a map for determining a first fuel injection correction amount QiscOFF1 when the clutch is off.
FIG. 9 is an explanatory diagram of a map structure for obtaining a fuel injection correction amount QiscON when the clutch is on.
10 is a timing chart showing an example of processing according to Embodiment 1. FIG.
FIG. 11 is a timing chart illustrating an example of processing according to the first embodiment.
12 is a flowchart of fuel injection amount control processing according to Embodiment 2. FIG.
FIG. 13 is a flowchart of a process for calculating fuel injection correction amounts QiscON1, QiscON2, QiscOFF1, and QiscOFF2.
FIG. 14 is a flowchart of a start assist correction amount attenuation process.
FIG. 15 is a flowchart of a start assist correction amount attenuation process.
FIG. 16 is a timing chart showing an example of processing according to the second embodiment.
FIG. 17 is a timing chart showing an example of processing according to the second embodiment.
[Explanation of symbols]
2 ... diesel engine, 4 ... injector, 4a ... solenoid valve, 6 ... common rail, 8 ... supply piping, 8a ... check valve, 10 ... supply pump, 10a ... discharge port, 10b ... suction port, 10c ... pressure control valve, DESCRIPTION OF SYMBOLS 10d ... Return port, 12 ... Fuel tank, 14 ... Filter, 16 ... Return piping, 18 ... Intake passage, 18a ... Intake valve, 20 ... Exhaust passage, 20a ... Exhaust valve, 22 ... Glow plug, 22a ... Glow relay, 24 Accelerator pedal, 26 ... Accelerator opening sensor, 30 ... Starter, 30a ... Starter state detection switch, 32 ... Water temperature sensor, 36 ... Fuel temperature sensor, 38 ... Fuel pressure sensor, 40 ... Engine rotation sensor, 42 ... Cylinder discrimination sensor, 44 ... clutch switch, 46 ... vehicle speed sensor, 52 ... ECU.

Claims (9)

An internal combustion engine output control device that executes an output increase correction process by a start assist correction when starting a vehicle with respect to an internal combustion engine for driving a vehicle,
The internal combustion engine operation region is divided into a plurality of regions, and the region-attached output correction amount to be calculated is provided for each internal combustion engine operation region, and the start assist correction is executed based on the total amount of the region-attached output correction amount. An internal combustion engine output control apparatus comprising: output correction means for switching a gain when calculating the region-attached output correction amount in accordance with each internal combustion engine operation region. 2. The internal combustion engine output control device according to claim 1, wherein the gain is one or both of a gain when the region-attached output correction amount is obtained by a calculation formula and a gain when the gain is obtained from a map. In Claim 1 or 2, the output correction means divides the internal combustion engine operation region into a first region at the time of idling stop, a second region at the time of start, and a third region other than these, The gain for calculating the region-attached output correction amount for the second region is compared with each gain for calculating the region-attached output correction amount for the first region and the region-attached output correction amount for the third region. An internal combustion engine output control device characterized by being set large. 3. The output correction means according to claim 1, wherein the output correction means includes a first region where the clutch is engaged and the vehicle is stopped, a second region where the clutch is released, and a clutch is engaged. Divided into the third region where the vehicle is traveling, and compared with each gain when calculating the region-attached output correction amount of the first region and the region-attached output correction amount of the third region, An internal combustion engine output control device characterized in that a gain for calculating the region-attached output correction amount of two regions is set large. 5. The gain in calculating the region attached output correction amount in the third region is set smaller than the gain in calculating the region attached output correction amount in the first region. An internal combustion engine output control device. 3. The output correction means according to claim 1, wherein the output correction means includes a first area where the clutch is engaged and stopped, a second area where the clutch is released and stopped, and the clutch is released. The third region that is traveling and the fourth region that is traveling with the clutch engaged, and the region-attached output correction amount of the first region, the region-attached output correction amount of the third region, and the An internal combustion engine characterized in that a gain for calculating the region-attached output correction amount for the second region is set larger than each gain for calculating the region-attached output correction amount for the fourth region. Engine output control device. 7. The region-attached output correction amount for the first region, the region-attached output correction amount for the third region, and the region-attached output correction amount for the fourth region, or the region-attached output correction for the third region. The gain for calculating each region-attached output correction amount is set to be smaller in the order of the amount, the region-attached output correction amount of the first region, and the region-attached output correction amount of the fourth region. Internal combustion engine output control device. 8. An output correction amount attenuating means for attenuating an output correction amount that is no longer necessary as start assist in an operating state where no acceleration request is required or in an internal combustion engine operation region where start assist correction is not executed. An internal combustion engine output control device. 9. The internal combustion engine output control device according to claim 1, wherein the internal combustion engine is a diesel engine, and the output increase correction process is an increase correction of a fuel injection amount.

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