JP2841959B2 - Fuel injection control system for diesel engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diesel engine applied to, for example, an automobile, and more particularly, to a fuel injection amount for controlling a fuel injection amount so as to reduce a shift shock of an automatic transmission connected to the diesel engine. The present invention relates to a control device.

[0002]

2. Description of the Related Art Conventionally, various proposals have been made for controlling the fuel injection amount of a diesel engine.
Japanese Patent Application Laid-Open No. 3-1738 discloses a technique of a fuel injection amount control method for smoothly shifting an automatic transmission. That is, according to this conventional technique, in an electronically controlled diesel engine, when a predetermined shift is performed in an automatic transmission, the fuel injection amount is changed so as to reduce the output torque difference before and after the shift to reduce the shift shock. I was On the other hand, for example, in Japanese Patent Application Laid-Open No. 60-156950, in an electronically controlled diesel engine, in order to prevent an acceleration shock, a sudden change in the fuel injection amount during acceleration is suppressed, and the fuel injection amount obtained from the operating state of the engine is suppressed. Is performed to perform "smoothing control" for gradually increasing the amount. Japanese Patent Application Laid-Open No. 1-271626 discloses performing "smoothing control" in which the fuel injection amount is gradually reduced during deceleration in order to prevent a deceleration shock.

In order to satisfy the requirement for smooth shifting of the automatic transmission and the prevention of acceleration shock and deceleration shock, it is conceivable to combine the above-mentioned prior arts.

[0004]

However, when the above-mentioned prior arts are combined, when the fuel injection amount is reduced so as to immediately reduce the output torque at the time of gear shifting,
"Smoothing control" for gradually reducing the injection amount is executed. For example, an electronic control unit (Electronic Control Unit, hereinafter referred to as "ECU") for controlling an electronically controlled automatic transmission (Electronic Controlled Transmission, hereinafter referred to as "ECT"), that is, an ECT ECU, and an engine E by integrated control with the engine ECU for controlling
When CT and the diesel engine are controlled, E
Even when the fuel injection amount of the diesel engine is reduced so as to reduce the output torque in response to a request from the CT ECU to the engine ECU, the “smoothing control” of the injection amount is executed. Therefore, there is a possibility that the output torque does not immediately decrease but slowly decreases, and it is difficult to reduce the shift shock.

The present invention has been made in view of the above-mentioned circumstances, and has as its object to reduce the fuel injection amount at the time of shifting of an automatic transmission and gradually increase or decrease the fuel injection amount at the time of acceleration / deceleration. It is an object of the present invention to provide a fuel injection amount control device for a diesel engine capable of appropriately reducing a shift shock of an automatic transmission.

[0006]

In order to achieve the above-mentioned object, according to the present invention, as shown in FIG. 1, an automatic transmission M2 connected to a diesel engine M1 for switching a shift state is provided. A shift determining means M3 for determining a shift change of the automatic transmission M2; a fuel injection means M4 for injecting fuel into the diesel engine M1;
1, an operating state detecting means M5 for detecting an operating state, an injection amount calculating means M6 for calculating a fuel injection amount to be injected into the diesel engine M1 based on a detection result of the operating state detecting means M5, and an injection amount calculating means An injection control means M7 for drivingly controlling the fuel injection means M4 based on the calculation result of M6,
When the shift determining means M3 determines that the shift of the automatic transmission M2 is to be switched, the shift time reduction correcting means M8 for reducing the calculation result by the injection amount calculating means M6 to reduce the shift shock and the calculation by the injection amount calculating means M6. A fuel injection amount control device for a diesel engine, comprising: an injection amount smoothing correction unit M9 for gradually increasing or decreasing the fuel injection amount until the calculation result when the fuel injection amount to be changed changes.
During the weight loss correction of shifting time decrease correction means M8, moderation to prohibit the operation of the injection amount of better correction means M9 correction prohibition means M
10 are provided.

[0007]

According to the above construction, as shown in FIG. 1, during the operation of the diesel engine M1, the operating state detecting means M is operated.
5 detects the operating state of the diesel engine M1. Based on the detection result, the injection amount calculating means M6 calculates the fuel injection amount to be injected into the diesel engine M1. Further, based on the calculation result, the injection control means M7 controls the driving of the fuel injection means M4.

Further, the shift determining means M3 is provided with an automatic transmission M2.
Of the automatic transmission M
In the case of the shift change of No. 2, the shift amount reduction correcting means M
8 corrects the result of calculation by the injection amount calculating means M6 by reducing the amount,
As a result, the shift shock of the automatic transmission M2 is reduced. On the other hand, when the fuel injection amount calculated by the injection amount calculation means M6 changes, the injection amount smoothing correction means M9 changes.
The fuel injection amount is gradually increased or decreased until the calculation result, thereby suppressing a sudden change in the fuel injection amount.

[0009] Then, smoothing correction inhibiting means M10 is, during the weight loss correction of shifting time decrease correction means M8, prohibits the operation of the injection amount of better correction means M9, shifting time decrease correction means M8
And the injection amount smoothing correction means M9 are not operated at the same time.

Therefore, when the shift of the automatic transmission M2 is switched, the fuel injection amount to be injected into the diesel engine M1 is corrected to be reduced, but the injection amount at that time is immediately reduced without being gradually reduced. Weight loss.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which a fuel injection amount control device for a diesel engine according to the present invention is embodied in an automobile will be described in detail with reference to the drawings.

FIG. 2 is a schematic diagram showing a fuel injection amount control device for a supercharged diesel engine (engine) according to this embodiment. FIG. 3 shows a distribution type fuel injection pump 1 constituting the fuel injection means. FIG. The fuel injection pump 1 includes a drive pulley 3 which is drivingly connected to a crankshaft 40 of the diesel engine 2 via a belt or the like. The fuel injection pump 1 is driven by the rotation of the drive pulley 3, and the fuel is injected under pressure to each fuel injection nozzle 4 provided for each cylinder (four cylinders in this case) of the diesel engine 2 to perform fuel injection. .

In the fuel injection pump 1, a drive pulley 3 is attached to a tip of a drive shaft 5.
In the middle of the drive shaft 5, there is provided a fuel feed pump (developed at 90 degrees in this figure) 6 composed of a vane type pump. Further, a disk-shaped pulser 7 is attached to the base end side of the drive shaft 5. The outer surface of the pulsar 7 has a diesel engine 2
In this case, four cutting teeth are formed at equal angular intervals, that is, four cutting teeth are formed at equal angular intervals, and between each cutting tooth, 14 (total of 56) projections are formed at equal angular intervals. I have. The base end of the drive shaft 5 is connected to the cam plate 8 via a coupling (not shown).

A roller ring 9 is provided between the pulsar 7 and the cam plate 8, and a plurality of cam rollers 10 facing the cam face 8a of the cam plate 8 are mounted along the circumference of the roller ring 9. I have. Cam face 8
a is provided as many as the number of cylinders of the diesel engine 2. The cam plate 8 is always urged and engaged with the cam roller 10 by the spring 11.

A base end of a fuel pressurizing plunger 12 is attached to the cam plate 8 so as to be integrally rotatable. The cam plate 8 and the plunger 12 are rotated in conjunction with the rotation of the drive shaft 5. That is, the rotational force of the drive shaft 5 is transmitted to the cam plate 8 via the coupling, so that the cam plate 8 rotates and engages with the cam roller 10 to reciprocate in the left-right direction by the same number as the number of cylinders. Driven. Further, the plunger 12 is driven to reciprocate in the same direction while rotating with the reciprocation. That is,
The plunger 12 is moved forward (lift) while the cam face 8a of the cam plate 8 rides on the cam roller 10 of the roller ring 9, and conversely, the plunger 12 is moved back while the cam face 8a rides down the cam roller 10.

The plunger 12 is fitted into a cylinder 14 formed in the pump housing 13, and a high pressure chamber 15 is formed between the tip of the plunger 12 and the bottom of the cylinder 14.
It has become. Also, on the outer periphery of the tip side of the plunger 12,
The same number of intake grooves 16 and distribution ports 17 as the number of cylinders of the diesel engine 2 are formed. In addition, these suction grooves 16
And the pump housing 13 corresponding to the distribution port 17.
Is formed with a distribution passage 18 and a suction port 19.

When the drive shaft 5 is rotated to drive the fuel feed pump 6, fuel is supplied from a fuel tank (not shown) into the fuel chamber 21 through the fuel supply port 20. Also, during the suction stroke in which the plunger 12 is moved back and the high-pressure chamber 15 is depressurized, the suction groove 1
The fuel is introduced from the fuel chamber 21 to the high-pressure chamber 15 when one of the ports 6 communicates with the suction port 19. On the other hand, during the compression stroke in which the plunger 12 is moved forward and the high-pressure chamber 15 is pressurized, fuel is pressure-fed from the distribution passage 18 to the fuel injection nozzle 4 of each cylinder and injected.

The pump housing 13 is provided with a spill passage 22 for fuel spill that connects the high-pressure chamber 15 and the fuel chamber 21. An electromagnetic spill valve 23 as a spill adjusting valve for adjusting the fuel spill from the high-pressure chamber 15 is provided in the middle of the spill passage 22. The electromagnetic spill valve 23 is a normally open type valve. When the coil 24 is not energized (off), the valve body 25 is opened and fuel in the high-pressure chamber 15 is spilled to the fuel chamber 21. When the coil 24 is energized (turned on), the valve body 25 is closed, and the spill of fuel from the high-pressure chamber 15 to the fuel chamber 21 is stopped.

Accordingly, by controlling the energization time of the electromagnetic spill valve 23, the valve 23 is controlled to close and open, and the spill amount of fuel from the high-pressure chamber 15 to the fuel chamber 21 is adjusted. Then, by opening the electromagnetic spill valve 23 during the compression stroke of the plunger 12, the fuel in the high-pressure chamber 15 is reduced in pressure, and the fuel injection from the fuel injection nozzle 4 is stopped. That is, even when the plunger 12 moves forward, the fuel pressure in the high-pressure chamber 15 does not increase while the electromagnetic spill valve 23 is open, and the fuel injection from the fuel injection nozzle 4 is not performed. Further, during the forward movement of the plunger 12, by controlling the timing of closing and opening the electromagnetic spill valve 23, the amount of fuel injected from the fuel injection nozzle 4 is controlled.

Below the pump housing 13, there is provided a timer device (expanded 90 degrees in this figure) 26 for adjusting the fuel injection timing. The timer device 26 changes the position of the roller ring 9 with respect to the rotation direction of the drive shaft 5, thereby changing the timing at which the cam face 8a engages with the cam roller 10, that is, the reciprocating drive timing of the cam plate 8 and the plunger 12. It is for.

The timer device 26 is driven by hydraulic pressure. A timer housing 27, a timer piston 28 fitted in the housing 27, and a low pressure chamber 29 on one side of the timer housing 27. A timer spring 31 for urging the piston 28 toward the other pressurizing chamber 30 is provided. The timer piston 28 is connected to the roller ring 9 via a slide pin 32.

In the pressurizing chamber 30 of the timer housing 27,
The fuel pressurized by the fuel feed pump 6 is introduced. The position of the timer piston 28 is determined by the balance between the fuel pressure and the urging force of the timer spring 31. Further, the position of the roller ring 9 is determined by determining the position of the timer piston 28, and the plunger 1 is moved through the cam plate 8.
2 is determined.

The timer device 26 is provided with a timing control valve 33 for adjusting the fuel pressure of the timer device 26, that is, the control oil pressure. That is, the pressurizing chamber 30 and the low-pressure chamber 29 of the timer housing 27
The timing control valve 33 is provided in the middle of the communication passage 34. The timing control valve 33 is an electromagnetic valve whose opening and closing are controlled by a duty-controlled energization signal, and the fuel pressure in the pressurizing chamber 30 is adjusted by controlling the opening and closing of the valve 33. Then, the lift timing of the plunger 12 is controlled by adjusting the fuel pressure, and the fuel injection timing from each fuel injection nozzle 4 is adjusted.

On the upper part of the roller ring 9, a rotation speed sensor 35 composed of an electromagnetic pickup coil is mounted so as to face the outer peripheral surface of the pulser 7. This rotation speed sensor 35
Detects the passage of a projection or the like of the pulsar 7 when they cross, and outputs a timing signal (engine rotation pulse) corresponding to the engine speed NE. Further, since the rotation speed sensor 35 is integrated with the roller ring 9, the rotation speed sensor 35 outputs a reference timing signal to the plunger lift at a constant timing regardless of the control operation of the timer device 26.

Next, the diesel engine 2 will be described. In the diesel engine 2, a main combustion chamber 44 corresponding to each cylinder is formed by the cylinder 41, the piston 42, and the cylinder head 43. or,
Each of the main combustion chambers 44 is connected to a sub-combustion chamber 45 provided correspondingly for each cylinder. Then, the fuel injected from each fuel injection nozzle 4 is supplied to each sub combustion chamber 45. Further, a well-known glow plug 46 as a start-up assist device is attached to each sub-combustion chamber 45.

The diesel engine 2 is provided with an intake pipe 47 and an exhaust pipe 50, respectively. Its intake pipe 4
7 is provided with a compressor 49 of a turbocharger 48 constituting a supercharger. The exhaust pipe 50 is provided with a turbine 51 of a turbocharger 48. Further, the exhaust pipe 50 is provided with a waste gate valve 52 for adjusting the supercharging pressure PiM. As is well known, the turbocharger 48 uses the energy of the exhaust gas to rotate the turbine 51, and rotates the compressor 49 on the same axis to increase the pressure of the intake air.
Thus, a high-density air-fuel mixture is sent into the main combustion chamber 44 to burn a large amount of fuel, thereby increasing the output of the diesel engine 2.

The diesel engine 2 has an exhaust pipe 5
A recirculation pipe 54 is provided for recirculating a part of the exhaust gas in the cylinder 0 to the suction port 53 of the intake pipe 47. An exhaust gas recirculation valve (EGR valve) 55 for adjusting the amount of exhaust gas recirculation is provided in the middle of the recirculation pipe 54.
Is provided. The opening and closing of the EGR valve 55 is controlled by the control of a vacuum switching valve (VSV) 56.

Further, a throttle valve 58 is provided in the middle of the intake pipe 47 so as to open and close in accordance with the amount of depression of an accelerator pedal 57. Also, its throttle valve 5
A bypass passage 59 is provided in parallel with 8, and a bypass throttle valve 60 is provided in the bypass passage 59. The opening and closing of the bypass throttle valve 60 is controlled by an actuator 63 having a two-stage diaphragm chamber driven by control of two VSVs 61 and 62. The opening and closing of the bypass throttle valve 60 is controlled in accordance with various operation states. For example, it is controlled to a half-open state during idle operation to reduce noise and vibration, to a fully opened state during normal operation, and to a fully closed state during smooth operation to stop smoothly.

The electromagnetic spill valve 2 provided in the fuel injection pump 1 and the diesel engine 2 as described above
3. The timing control valve 33, the glow plug 46 and each of the VSVs 56, 61, 62 constitute an engine constituting an injection amount calculating means, an injection control means, a shift reduction correction means, an injection quantity smoothing correction means and a smoothing correction inhibiting means. Electronic control unit (engine electronic control unit, hereinafter simply referred to as “engine ECU”) 7
1 and electrically connected to the engine ECU 7
1 controls their drive timing.

As sensors constituting the operating state detecting means, the following various sensors are provided in addition to the rotation speed sensor 35. That is, an intake air temperature sensor 7 for detecting an intake air temperature THA near the air cleaner 64 is provided in the intake pipe 47.
2 are provided. Further, an accelerator opening sensor 73 for detecting the accelerator opening ACCP corresponding to the load of the diesel engine 2 from the open / close position of the throttle valve 58 is provided. An intake pressure sensor 74 for detecting the intake air pressure after supercharging by the turbocharger 48, that is, the supercharging pressure PiM is provided near the intake port 53. Further, the cooling water temperature TH of the diesel engine 2
A water temperature sensor 75 for detecting W is provided. Also, the reference position of rotation of the crankshaft 40 of the diesel engine 2,
For example, a crank angle sensor 76 that detects a rotational position of the crankshaft 40 with respect to the top dead center of a specific cylinder and outputs a crank angle signal GS is provided. In addition, the electronic control type automatic transmission 65 which is connected to the diesel engine 2 and switches the gear change state has a reed switch 77b turned on / off by a magnet 77a rotated by the rotation of the gear to change the vehicle speed (vehicle speed). ) A vehicle speed sensor 77 for detecting SP is provided.

The engine ECU 71 is connected to the above-described sensors 72 to 77, respectively, and also connected to the rotation speed sensor 35. Also, the engine ECU 7
Reference numeral 1 denotes an electromagnetic spill valve 23, a timing control valve 33, a glow plug 46, and VSVs 56, 61, 62 based on signals output from the sensors 35, 72 to 77.
Etc. are suitably controlled.

As described above, in this embodiment, the engine ECU 71 is a control device mainly responsible for the fuel injection amount control, the fuel injection timing control, the supercharging pressure control and the like of the diesel engine 2. In addition to this, in this embodiment, as shown in FIG. 2, an electric controlled transmission (ECT) ECU 78 that controls the automatic transmission 65 and constitutes a shift determining means thereof is provided.

In this embodiment, the ECT ECU 78 controls the direct coupling clutch control and the shift control of the automatic transmission 65,
In order to reduce the shift shock of the automatic transmission 65, the torque of the diesel engine 2 is intentionally fluctuated by, for example, a shift control torque reduction. Therefore, ECTCU7
8 receives a shift position signal from a shift position sensor 79 provided in the automatic transmission 65 and detecting the shift position. The ECT ECU 78 exchanges signals with the engine ECU 71, and inputs the detection values of the sensors 35, 73, 75, and 77 from the engine ECU 71 as data signals. Then, the ECT ECU 78 determines a shift pattern according to the shift condition at each time based on the input various signals, and outputs a shift control signal for suitably controlling the actuator of the automatic transmission 65 according to the shift pattern. . At the same time, E
The CT ECU 78 outputs to the engine ECU 71 a shifting signal (torque controlling signal) for shifting the automatic transmission 65 and a torque control request injection amount signal.

Next, the configuration of the engine ECU 71 will be described with reference to the block diagram of FIG. The engine ECU 71 includes a central processing unit (CPU) 81, a read-only memory (ROM) 82 in which a predetermined control program, a map, and the like are stored in advance, a random access memory (RAM) 83, in which calculation results of the CPU 81 and the like are temporarily stored, A backup RAM 84 and the like for storing the data, and a logical operation circuit in which these components are connected to an input port 85 and an output port 86 by a bus 87.

The input port 85 is provided with the above-described intake air temperature sensor 72, accelerator opening sensor 73, intake pressure sensor 74, and water temperature sensor 75 in the buffers 88, 89, 90, and 9 respectively.
1, a multiplexer 92 and an A / D converter 93. Similarly, the input port 85 is connected to the rotation speed sensor 35, the crank angle sensor 76, and the vehicle speed sensor 77 via a waveform shaping circuit 95. Then, the CPU 81 reads, as input values, detection signals of the sensors 35, 72 to 77, etc., which are input through the input port 85. Each drive circuit 9 is connected to the output port 86.
The electromagnetic spill valve 23, the timing control valve 33, the glow plug 46, the VSVs 56, 61, 62 and the like are connected via 6, 97, 98, 99, 100, 101.

The CPU 81 controls the sensors 35 and 72
Based on the input value read from ~ 77, the electromagnetic spill valve 2
3. The timing control valve 33, the glow plug 46, and the VSVs 56, 61, 62 are suitably controlled.

Further, the engine ECU 71 is connected to the input port 8
5 and the output port 86, exchanges data with the ECT ECU 78, such as detection values and calculation results of the sensors 35, 72, 75, and 77, a signal during shifting, and a torque control request injection amount signal.

Next, the processing operation of the fuel injection amount control executed by the engine ECU 71 will be described with reference to FIGS. The flowcharts shown in FIGS. 5 and 6 are main routines for controlling the fuel injection amount in the fuel injection pump 1 among the processes executed by the engine ECU 71, and are executed after a predetermined engine rotation pulse interruption.

When the process proceeds to this routine, first, at step 101, the engine speed NE, the accelerator opening ACCP and the engine speed NE are determined based on the detected values from the rotation speed sensor 35, the accelerator opening sensor 73, and the intake pressure sensor 74. The supply pressure PiM and the like are read. At the same time, E
The communication data such as the signal during the shift and the torque control request injection amount signal from the CTEC 78 are read.

Next, at step 102, the previously read engine speed NE and accelerator opening ACCP are read.
Based on the above, the basic fuel injection amount QBASE is calculated. That is, the calculation of the basic injection amount QBASE is performed with reference to a predetermined map (not shown) using the engine speed NE and the accelerator opening ACCP as parameters.
Further, in the calculation of the basic injection amount QBASE, a low-temperature start increase correction, a rapid deceleration increase correction, and the like are performed as necessary based on respective values such as the cooling water temperature THW, the accelerator opening ACCP, and the engine speed NE.

Subsequently, in step 103, the maximum injection amount QFULL in the current control cycle is calculated based on the previously read engine speed NE and supercharging pressure PiM.

Further, in step 104, ECTE
Based on the communication data of the CU 78, the shift request injection amount Q
Calculate ECT. That is, the communication data is sent from the ECT ECU 78 to the engine ECU 71 in response to the shift or non-shift of the automatic transmission 65. The engine ECU 71 performs torque control appropriate for the shift or non-shift based on the communication data. Shift required injection amount QECT is calculated.

Subsequently, at step 105, ECT
Based on the communication data from the ECU 78, the automatic transmission 65
It is determined whether or not the shift is being performed. Here, when the automatic transmission 65 is shifting, it is determined in step 106 whether or not the previously calculated shift required injection amount QECT is larger than the basic injection amount QBASE.

If it is determined in step 106 that the required shift amount QECT is not larger than the basic injection amount QBASE, then in step 107, the smaller required shift amount QECT is changed to the basic injection amount QBASE.
And the process proceeds to step 108.

On the other hand, if it is determined in step 105 that the automatic transmission 65 is not shifting, or in step 106, the shift required injection amount QECT is changed to the basic injection amount QBASE.
If it is larger, the process directly proceeds to step 108.

That is, steps 105 to 107
In the process (1), the smaller of the calculated basic injection amount QBASE and the shift request injection amount QECT is selected. Then, Step 105, Step 106 or Step 1
07, and in step 108, the ECTE
Based on the communication data from the CU 78, it is determined whether or not the automatic transmission 65 is shifting gears. Here, the automatic transmission 6
If it is not during the speed change of step 5, in step 109,
It is determined whether or not the previously obtained basic injection amount QBASE is larger than the final injection amount QFIN0 in the previous control cycle. That is, it is determined whether or not the currently calculated basic injection amount QBASE is larger than the last final injection amount QFIN0.

If it is determined in step 109 that the basic injection amount QBASE is not larger than the last final injection amount QFIN0, then in step 110, the basic injection amount QBASE is reduced by a predetermined amount from the last final injection amount QFIN0. It is determined whether the value is larger than the result of subtracting the value β. That is, it is determined whether or not the current decrease in the basic injection amount QBASE is greater than the deceleration smoothing value β. If the current decrease in the basic injection amount QBASE is larger than the deceleration smoothing value β, in step 111, the result obtained by subtracting the deceleration smoothing value β from the last final injection amount QFIN0 is used as the final basic injection amount QBASE1. And the process proceeds to step 115.

If the basic injection amount QBASE is larger than the last final injection amount QFIN0 in step 109, the basic injection amount QBASE is increased in step 112.
It is determined whether or not BASE is smaller than a result of adding a predetermined acceleration smoothing value α to the last final injection amount QFIN0. That is, it is determined whether or not the increment of the basic injection amount QBASE this time is larger than the acceleration smoothing value α.
If the current increase in the basic injection amount QBASE is larger than the acceleration smoothing value α, in step 113, the result obtained by adding the acceleration smoothing value α to the last final injection amount QFIN0 is the final basic injection amount QBASE1. And the process moves to step 115.

In step 110, if the current decrease in the basic injection amount QBASE is not greater than the deceleration smoothing value β, or in step 112, the current increase in the basic injection amount QBASE is increased to the acceleration smoothing value α. Otherwise, in each step 114,
The basic injection amount QBASE is used as it is as the final basic injection amount QBA.
After setting as SE1, the process proceeds to step 115.

On the other hand, if it is determined in step 108 that the automatic transmission 65 is shifting, in step 114, the previously determined basic injection amount QBASE is set as it is as the final basic injection amount QBASE1, and then to step 115. Transition.

That is, steps 108 to 114
When the automatic transmission 65 is not shifting, the acceleration shock or the deceleration shock during acceleration / deceleration is suppressed based on the magnitude relationship between the final injection amount QFIN0 in the previous control cycle and the basic injection amount QBASE obtained this time. Therefore, the "smoothing control" for suppressing a sudden change in the injection amount as the final basic injection amount QBASE1 by gradually increasing or decreasing the basic injection amount QBASE is performed. In contrast, the automatic transmission 65
When the shift is being performed, the basic injection amount QBASE is used as it is as the final basic injection amount QBASE1, and the "smoothing control" of the injection amount is prohibited. Similarly, even when the automatic transmission 65 is not shifting, if the change amount of the basic injection amount QBASE obtained this time is small, the “smoothing control” of the injection amount is stopped.

Then, Step 111, Step 113
Alternatively, the process proceeds from step 114 to step 115 in which the previously set final basic injection amount QBASE1 is
It is determined whether or not it is smaller than the previously calculated maximum injection amount QFULL.

If the final basic injection amount QBASE1 is smaller than the maximum injection amount QFULL, step 1
At 16, the final basic injection amount QBASE1 is set as the final injection amount QFIN. Subsequently, at step 117, an injection amount command value TSP corresponding to the final injection amount QFIN is obtained. Then, in step 118,
The calculated injection amount command value TSP is output, that is, the injection amount command value TSP corresponding to the final basic injection amount QBASE1.
The electromagnetic spill valve 23 is drive-controlled based on. Finally,
In step 119, the final injection amount QFIN in the current control cycle is changed to the final injection amount QFI in the previous control cycle.
It is set as N0, and the subsequent processing ends once.

On the other hand, if the final basic injection amount QBASE1 is not smaller than the maximum injection amount QFULL in step 115, the maximum injection amount QFULL is set as the final injection amount QFIN in step 120. or,
In step 117, an injection amount command value TSP corresponding to the final injection amount QFIN is obtained. In step 118, the obtained injection amount command value TSP is output, that is, the drive control of the electromagnetic spill valve 23 is performed based on the injection command value TSP corresponding to the maximum injection amount QFULL.
Finally, at step 119, the final injection amount Q
FIN is set as the last final injection amount QFIN0, and the subsequent processing is temporarily ended.

That is, steps 114 to 120
In this process, the smaller of the final basic injection amount QBASE1 and the maximum injection amount QFULL is selected, and fuel injection is executed.

As described above, according to the fuel injection amount control device of this embodiment, the shift request injection is performed by the engine ECU 71 based on the communication data from the ECT ECU 78 in order to reduce the shift shock when the automatic transmission 65 shifts. The amount QECT is calculated, and the fuel injection amount is controlled in accordance with the shift required injection amount QECT corrected for the decrease. or,
In order to prevent an acceleration shock or a deceleration shock, "smoothing control" is performed in which a sudden change in the fuel injection amount required at the time of acceleration / deceleration is suppressed and the final basic injection amount QBASE1 is gradually increased / decreased. Therefore, it is possible to achieve both smooth shifting of the automatic transmission and prevention of acceleration shock and deceleration shock.

Moreover, in this embodiment, the automatic transmission 65
During the shift, the "smoothing control" of the injection amount is prohibited. Therefore, when the automatic transmission 65 shifts, the fuel injection amount to be injected into the diesel engine 2 is reduced and corrected as the shift request injection amount QECT.
The injection amount at that time is immediately reduced without being gradually reduced. As a result, the output torque of the diesel engine 2 is immediately reduced by the torque control request from the ECT ECU 78 to the engine ECU 71 at the time of shifting, and the shift shock of the automatic transmission 65 can be appropriately reduced according to the torque control request. .

FIG. 7 is a time chart for explaining the relationship among changes in the output torque of the automatic transmission 65, the engine speed NE, the required shift injection amount QECT, the signal during shifting, and the output torque of the diesel engine 2.

In this figure, a solid line indicates a change in the present embodiment, and some broken lines indicate a change in the conventional example. In the figure,
At time t1, when the ECT ECU 78 makes a shift determination to shift the automatic transmission 65, the shift request injection amount QECT calculated by the engine ECU 71 becomes smaller at that point in time. The required injection amount QECT is not used, and the injection amount decrease correction is not performed. Thereafter, when a predetermined time for preparing for gear shifting has elapsed, gear shifting is started, and the engine speed NE decreases.

Thereafter, at time t2, it is detected that the engine speed NE has started to decrease, and the in-shift signal changes from "low" to "high". When the shifting signal changes to “high”, the engine ECU 71 requests the shift request injection amount QEC.
Since the injection amount reduction correction is performed by using T, and the “smoothing control” of the injection amount is prohibited, the output torque of the diesel engine 2 immediately decreases. Therefore, at this time, the output torque of the automatic transmission 65 is suppressed from sharply increasing.

After a short period of time before the end of the shift of the automatic transmission 65 at time t3, the required shift injection amount QECT returns to a value before the shift with a certain gradient, and the output of the diesel engine 2 is accordingly increased. The torque starts to rise. When the output torque of the diesel engine 2 rises and returns to the original level, the injection amount reduction correction ends, and the shifting signal changes from “high” to “low” at time t4, while the automatic transmission 65 changes. Output torque decreases with an increase in the fuel injection amount, and the shift ends.

As can be seen from this figure, in this embodiment, the engine ECU 71
The injection amount calculated in (1) is reduced, but the "smoothing control" of the injection amount is prohibited. Therefore, the output torque of the diesel engine 2 immediately decreases at the start of the shift, and returns to almost the same level as before the shift at the end of the shift. On the other hand, in the conventional example, the diesel engine 2
Of the output torque is delayed at the start of the shift, and delayed at the end of the shift. Therefore, it is clear that the fuel injection amount control of the present embodiment is more advantageous and appropriate from the viewpoint of reducing the shift shock early.

It should be noted that the present invention is not limited to the above-described embodiment, and may be carried out as follows by appropriately changing a part of the configuration without departing from the spirit of the invention. (1) In the above embodiment, the ECT ECU 78 for controlling the shift of the automatic transmission 65 is provided as the shift determining means for determining the shift change of the automatic transmission 65. However, the shift determination may be performed by the engine ECU 71. .

(2) In the above embodiment, the diesel engine 2 provided with the turbocharger 48 as the supercharger is embodied. However, the present invention is embodied as the diesel engine provided with the supercharger as the supercharger or the supercharger. It can also be embodied in a diesel engine not equipped with.

[0065]

As described above in detail, according to the present invention, at the time of shifting of an automatic transmission connected to a diesel engine, the fuel injection amount calculated according to the operating state is reduced in order to reduce the shift shock. In the fuel injection amount control device, when the acceleration and deceleration of the diesel engine is corrected, the fuel injection amount calculated according to the operation state is gradually increased or decreased to suppress the sudden change in the acceleration and deceleration and the smoothing control is performed.
During shifts in which the fuel injection amount is to be reduced, the smoothing control of the injection amount is prohibited.Therefore, the fuel injection amount to be injected into the diesel engine during the shift is reduced and corrected. Is quickly reduced without being gradually reduced, and has an excellent effect that shift shock of the automatic transmission can be appropriately reduced.

[Brief description of the drawings]

FIG. 1 is a conceptual configuration diagram of the present invention.

FIG. 2 is a schematic configuration diagram showing a fuel injection amount control device for a supercharged diesel engine according to an embodiment of the present invention;

FIG. 3 is a sectional view showing a fuel injection pump according to one embodiment.

FIG. 4 is a block diagram illustrating a configuration and the like of an engine ECU according to an embodiment.

FIG. 5 is a flowchart illustrating a main routine for a fuel injection amount control process executed by an engine ECU in one embodiment.

FIG. 6 is a flowchart illustrating a main routine for a fuel injection amount control process similarly executed by an engine ECU in one embodiment.

FIG. 7 is a time chart illustrating the relationship among changes in the output torque of the automatic transmission, the engine speed, the required shift injection amount, the shifting signal, and the output torque of the diesel engine in one embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Fuel injection pump as a fuel injection means, 2 ... Diesel engine, 65 ... Automatic transmission, 71 ... Injection amount calculation means, injection control means, shift reduction correction means, injection amount smoothing correction means, and smoothing correction inhibition Engine E constituting means
CU, 35: a rotational speed sensor, 73: an accelerator opening sensor, 74: an intake pressure sensor (35, 73, 74, etc. constitute operating state detecting means), 78: an ECT ECU as a shift determining means.

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Claims (1)

(57) [Claims] An automatic transmission connected to a diesel engine for switching a shift state; a shift determination unit for determining a shift change of the automatic transmission; a fuel injection unit for injecting fuel into the diesel engine; Operating state detecting means for detecting an operating state of the diesel engine; injection amount calculating means for calculating a fuel injection amount to be injected into the diesel engine based on a detection result of the operating state detecting means; and An injection control means for driving and controlling the fuel injection means based on the calculation result; and a shift reduction means for reducing the calculation result by the injection amount calculation means to reduce a shift shock when the shift determination means determines that the shift of the automatic transmission should be switched. When the fuel injection amount calculated by the shift amount calculating means changes, the calculation result is calculated. The fuel injection quantity control device for a diesel engine having an injection quantity smoothing correction means gradually increases or decreases corrected amount of fuel injection to said during decreasing correction of shifting time decrease correction unit, the injection quantity smoothing correction means A fuel injection amount control device for a diesel engine, characterized in that a smoothing correction prohibiting means for prohibiting the operation of the engine is provided.